Upgrade Example app to React-Native 0.78.1

[octavianduminicaconnatix]

What does this Pull Request do?

Upgrades the React-Native Example application to version 0.78.1 via https://react-native-community.github.io/upgrade-helper/

Thought Process

• I usually kept what I detected was added by us compared to the React-Native upgrade helper tool
• I removed the lines that were shown as removed in the upgrade helper. What is mentioned as removed below would be any line that existed only in our repository
• I added lines that were shown as added in the upgrade helper
• kept .env in .gitignore
• kept the reinstall script in package.json
• kept the purge_modules script in package.json
• kept the postinstall script in package.json
• kept the app specific dependencies and updated all to the latest versions
• kept the postinstall-postinstall dev dependency in package.json
• kept the react-native-dotenv dev dependency in package.json
• did not add the README.md
• removed the Java 1_8 compileOptions in app/build.gradle. I detected this was added by us and it is no longer present in the latest version
• removed copyDownloadableDepsToLibs Gradle task from app/build.gradle. I removed it since the helper removed other BUCK related files
• removed the applyNativeModulesAppBuildGradle at the end of app/build.gradle
• removed def REACT_NATIVE_VERSION from build.gradle
• removed the React-Native 0.70.14 specific patch
• temporary bump of google-cast-sdk in RNJWPlayer.podspec to 4.8.3 in order to solve a bundling issue of the Privacy Manifest. Context: The new React-Native generates a Privacy Manifest file at pod install which clashes with the one bundled by google-cast-sdk. Google released a fix for this in 4.8.3 and it is now declared as resource_bundles instead of resources in the Podspec file:
  Before: https://github.com/CocoaPods/Specs/blob/master/Specs/8/1/2/google-cast-sdk/4.8.1/google-cast-sdk.podspec.json
  After: https://github.com/CocoaPods/Specs/blob/master/Specs/8/1/2/google-cast-sdk/4.8.3/google-cast-sdk.podspec.json)

Why is this Pull Request needed?

To keep up to date to the latest React-Native changes

Are there any points in the code the reviewer needs to double check?

Double check against https://react-native-community.github.io/upgrade-helper/

Are there any Pull Requests open in other repos which need to be merged with this?

No

Addresses Issue(s):

GitHub Issue