Updated package preview version

Packages/manifest.json

     "com.unity.textmeshpro": "3.0.0-preview.1",
     "com.unity.timeline": "1.2.6",
     "com.unity.ugui": "1.0.0",
-    "com.unity.ui": "1.0.0-preview.5",
+    "com.unity.ui": "1.0.0-preview.6",
     "com.unity.ui.builder": "1.0.0-preview.3",
     "com.unity.vectorgraphics": "2.0.0-preview.12",
     "com.unity.modules.ai": "1.0.0",

Packages/packages-lock.json

         "com.unity.modules.unitywebrequest": "1.0.0",
         "com.unity.modules.unitywebrequestassetbundle": "1.0.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.cinemachine": {
       "version": "2.5.0",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ext.nunit": {
       "version": "1.0.0",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ide.rider": {
       "version": "2.0.5",
         "com.unity.test-framework": "1.1.1"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ide.visualstudio": {
       "version": "2.0.2",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ide.vscode": {
       "version": "1.2.1",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.postprocessing": {
       "version": "2.3.0",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.render-pipelines.core": {
       "version": "8.2.0",
         "com.unity.ugui": "1.0.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.render-pipelines.lightweight": {
       "version": "8.2.0",
         "com.unity.render-pipelines.universal": "8.2.0",
         "com.unity.postprocessing": "2.1.7"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.render-pipelines.universal": {
       "version": "8.2.0",
         "com.unity.render-pipelines.core": "8.2.0",
         "com.unity.shadergraph": "8.2.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.scriptablebuildpipeline": {
       "version": "1.9.0",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.searcher": {
       "version": "4.0.9",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.shadergraph": {
       "version": "8.2.0",
         "com.unity.render-pipelines.core": "8.2.0",
         "com.unity.searcher": "4.0.9"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.test-framework": {
       "version": "1.1.14",
         "com.unity.modules.imgui": "1.0.0",
         "com.unity.modules.jsonserialize": "1.0.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.textmeshpro": {
       "version": "3.0.0-preview.1",
         "com.unity.ugui": "1.0.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.timeline": {
       "version": "1.2.6",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ugui": {
       "version": "1.0.0",
       }
     },
     "com.unity.ui": {
-      "version": "1.0.0-preview.3",
+      "version": "1.0.0-preview.6",
       "depth": 0,
       "source": "registry",
       "dependencies": {
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.ui.builder": {
       "version": "1.0.0-preview.3",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.vectorgraphics": {
       "version": "2.0.0-preview.12",
         "com.unity.2d.sprite": "1.0.0",
         "com.unity.ugui": "1.0.0"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "nuget.castle-core": {
       "version": "1.0.1",
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "nuget.moq": {
       "version": "1.0.0",
         "nuget.castle-core": "1.0.1"
       },
-      "url": "https://packages.unity.com"
+      "url": "https://artifactory.prd.cds.internal.unity3d.com/artifactory/api/npm/upm-candidates"
     },
     "com.unity.modules.ai": {
       "version": "1.0.0",