Add publish option to release tooling

[paulb777]

Generate commands to publish a release to CocoaPods trunk.

Companion to internal cl/338150153.

Running with

--publish true
--log-only true
--git-root /path/to/firebase-ios-sdk

generates

pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/GoogleUtilities/7.0.0/GoogleUtilities.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/GoogleDataTransport/8.0.0/GoogleDataTransport.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseCoreDiagnostics/7.0.0/FirebaseCoreDiagnostics.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseCore/7.0.0/FirebaseCore.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseInstallations/7.0.0/FirebaseInstallations.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseInstanceID/7.0.0/FirebaseInstanceID.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/GoogleAppMeasurement/7.0.0/GoogleAppMeasurement.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseAnalytics/7.0.0/FirebaseAnalytics.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseABTesting/7.0.0/FirebaseABTesting.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseAppDistribution/7.0.0-beta/FirebaseAppDistribution.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseAuth/7.0.0/FirebaseAuth.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseCrashlytics/7.0.0/FirebaseCrashlytics.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseDatabase/7.0.0/FirebaseDatabase.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseDynamicLinks/7.0.0/FirebaseDynamicLinks.podspec.json
pod trunk push --skip-tests --synchronous --allow-warnings  ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseFirestore/7.0.0/FirebaseFirestore.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseFirestoreSwift/7.0.0-beta/FirebaseFirestoreSwift.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseFunctions/7.0.0/FirebaseFunctions.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseInAppMessaging/7.0.0-beta/FirebaseInAppMessaging.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseMessaging/7.0.0/FirebaseMessaging.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebasePerformance/7.0.0/FirebasePerformance.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseRemoteConfig/7.0.0/FirebaseRemoteConfig.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseStorage/7.0.0/FirebaseStorage.podspec.json
pod trunk push --skip-tests --synchronous   ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseStorageSwift/7.0.0-beta/FirebaseStorageSwift.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseMLCommon/7.0.0-beta/FirebaseMLCommon.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseMLModelInterpreter/7.0.0-beta/FirebaseMLModelInterpreter.podspec.json
pod trunk push --skip-tests --synchronous  -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/FirebaseMLVision/7.0.0-beta/FirebaseMLVision.podspec.json
pod trunk push --skip-tests --synchronous --allow-warnings -skip-import-validation ~/.cocoapods/repos/cpdc-internal-firebase/Specs/Firebase/7.0.0/Firebase.podspec.json

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Generated by 🚫 Danger

[ryanwilson]

Looks good, thanks! The one thing I think we can improve on for this and other related tools in the future (separate PR) is manual confirmation. Would be nice to print out the commands that will be run, along with a yes/no prompt for the release coordinator to validate beforehand.

[paulb777]

Agreed - Also we need to investigate how feasible it is to run the push commands from inside the tool versus printing them out to run separately. There may be Xcode interaction issues that are hard to resolve.

[ryanwilson]

From a user input standpoint, looks pretty trivial with readLine() https://developer.apple.com/documentation/swift/1641199-readline