revert TMP package update

Packages/manifest.json

     "com.unity.recorder": "2.1.0-preview.1",
     "com.unity.render-pipelines.universal": "7.2.1",
     "com.unity.terrain-tools": "3.0.1-preview",
-    "com.unity.textmeshpro": "3.0.0-preview.1",
+    "com.unity.textmeshpro": "2.1.0-preview.4",
     "com.unity.timeline": "1.2.11",
     "com.unity.ugui": "1.0.0",
     "net.peeweek.gameplay-ingredients": "https://github.com/peeweek/net.peeweek.gameplay-ingredients.git#2019.3.0",