ci: fix incorrect step names in sdk-release action
ci: fix incorrect step names in sdk-release action

Some of the step names were incorrect or misleading.

As an example, a step called "Merge back release commits to public/master repository" was actually creating and pushing an internal/release branch, NOT pushing to public/master. There were also other places that were incorrect, misleading, or unclear.

Also cleaned up some formatting and removed unnecessary `git fetch` commands because `git pull` performs the fetch on its own.

Also re-added `fetch-depth: 0` when checking out the public repo because it can't leak branches and I found an edge case when testing the Android SDK release action where it would sometimes fail at the final step without that option. I don't have evidence that the same issue can happen in the iOS SDK release action, but since we use the same final steps, it doesn't hurt the add the option back, and it may prevent future issues, I've re-added it just in case.
mParticle/mparticle-apple-sdk,mParticle/mparticle-apple-sdk,mParticle/mparticle-apple-sdk,mParticle/mparticle-apple-sdk,mParticle/mparticle-apple-sdk,mParticle/mparticle-apple-sdk