[android] 🤏 Update react-native-gesture-handler to 1.6.0 (expo#7121)

# Why

Part of expo#7006 

# How

- Used `et update-vendored-module` to update `react-native-gesture-handler`.
- Updated versions in some apps.
- Tried to run it on Android... and it turned out there is a new `RNGHModalUtils` file scoped under `com.facebook.react` package so I've copied this file manually to appropriate directory in `expoview`.
- Added a warning saying that `com.facebook.react` needs to be manually updated, we already do the same in `react-native-reanimated`.
- Added changelog entry.

# Test Plan

Tested examples in `native-component-list`.

package.json

@@ -49,7 +49,7 @@
     "react-native": "0.61.4",
     "react-native-appearance": "~0.2.1",
     "react-native-fade-in-image": "^1.5.0",
-    "react-native-gesture-handler": "~1.5.1",
+    "react-native-gesture-handler": "~1.6.0",
     "react-native-infinite-scroll-view": "^0.4.5",
     "react-native-maps": "0.26.1",
     "react-navigation": "4.1.0-alpha.1",