better testing sequence (#1076)

1. I didn't open the ios emulator at first, and nothing appeared. So I think we should add a step to open it to the sequence.
2. It's better to delete the app before installing it and not after. Otherwise on the first test, you might have troubles installing it.
3. Explicitly mention that Metro will be launched in step 4. I actually didn't notice metro was opened automatically, and tried running it myself.

Author: vzaidman

docs/guide-release-testing.md

@@ -99,37 +99,50 @@ Here are the 4 dimensions we cover in manual testing:
 **1. RNTester + iOS:**
 
 ```bash
+# 1. Open an iOS Emulator
+# 2. Kill Metro
+# 3. Remove any existing RNTester:
+xcrun simctl uninstall booted com.meta.RNTester.localDevelopment
+# 4. Build, install, and run RNTester + Metro:
 yarn test-release-local -t "RNTester" -p "iOS" -c $GITHUB_TOKEN
-# verify tests "what to test"
-# kill metro
-xcrun simctl uninstall booted com.meta.RNTester.localDevelopment # delete RNTester from your iOS simulator
+# 5. Verify tests "what to test"
 ```
 
 **2. RNTester + Android:**
 
 ```bash
+# 1. Open an Android Emulator
+# 2. Kill Metro
+# 3. Remove any existing RNTester:
+adb uninstall com.facebook.react.uiapp
+# 4. Build, install, and run RNTester + Metro:
 yarn test-release-local -t "RNTester" -p "Android" -c $GITHUB_TOKEN
-# verify tests "what to test"
-# kill metro
-adb uninstall com.facebook.react.uiapp # delete RNTester from your Android emulator
+# 5. Verify tests "what to test"
 ```
 
 **3. RNTestProject + iOS:**
 
 ```bash
+
+# 1. Open an iOS Emulator
+# 2. Kill Metro
+# 3. Remove any existing RNTestProject:
+xcrun simctl uninstall booted org.reactjs.native.example.RNTestProject
+# 4. Build, install, and run RNTestProject + Metro:
 yarn test-release-local -t "RNTestProject" -p "iOS" -c $GITHUB_TOKEN
-# verify tests "what to test"
-# kill metro
-xcrun simctl uninstall booted org.reactjs.native.example.RNTestProject # delete RNTestProject from your iOS simulator
+# 5. Verify tests "what to test"
 ```
 
 **4. RNTestProject + Android**
 
 ```bash
+# 1. Open an Android Emulator
+# 2. Kill Metro
+# 3. Remove any existing RNTestProject:
+adb uninstall com.rntestproject
+# 4. Build, install, and run RNTestProject + Metro:
 yarn test-release-local -t "RNTestProject" -p "Android" -c $GITHUB_TOKEN
-# verify tests "what to test"
-# kill metro
-adb uninstall com.rntestproject # delete RNTestProject from your Android emulator
+# 5. Verify tests "what to test"
 ```
 
 ## Testing Sequence (RN <= 0.78)