Adding explicit references to LWRP packages version 4.10.0-preview.

Packages/manifest.json

     "com.unity.collab-proxy": "1.2.16",
     "com.unity.package-manager-ui": "2.0.7",
     "com.unity.purchasing": "2.0.6",
-    "com.unity.render-pipelines.lightweight": "4.8.0-preview",
+    "com.unity.render-pipelines.core": "4.10.0-preview",
+    "com.unity.render-pipelines.lightweight": "4.10.0-preview",
+    "com.unity.shadergraph": "4.10.0-preview",
     "com.unity.subsystemregistration": "1.0.5",
     "com.unity.textmeshpro": "1.3.0",
     "com.unity.xr.arcore": "2.1.0-preview.1",