chore(CI): limit e2e runs to main branch only (#118)

We do not need them on labs, as they effectively don't check anything
right now & they still run on stacked PRs.

Main motivation here is resource saving, as we already have hit our
CI limit.

Author: kkafar

.github/workflows/android-e2e-test-fabric.yml

@@ -1,8 +1,8 @@
 name: Test Android e2e - new architecture
 on:
   pull_request:
-    branches-ignore:
-      - main-labs
+    branches:
+      - main
     paths:
       - '.github/workflows/android-e2e-test-fabric.yml'
       - 'package.json'

.github/workflows/android-e2e-test.yml

@@ -1,8 +1,8 @@
 name: Test Android e2e - old architecture
 on:
   pull_request:
-    branches-ignore:
-      - main-labs
+    branches:
+      - main
     paths:
       - '.github/workflows/android-e2e-test.yml'
       - 'package.json'

.github/workflows/ios-e2e-test-fabric.yml

@@ -1,8 +1,8 @@
 name: Test iOS e2e - new architecture
 on:
   pull_request:
-    branches-ignore:
-      - main-labs
+    branches:
+      - main
     paths:
       - '.github/workflows/ios-e2e-test-fabric.yml'
       - 'RNScreens.podspec'

.github/workflows/ios-e2e-test.yml

@@ -1,8 +1,8 @@
 name: Test iOS e2e - old architecture
 on:
   pull_request:
-    branches-ignore:
-      - main-labs
+    branches:
+      - main
     paths:
       - '.github/workflows/ios-e2e-test.yml'
       - 'RNScreens.podspec'