Modify CI to add a comment on successful run for dependabot

When CI successfully runs, the should be a comment about it.

With dependabot MRs, the latest commit is always the one for commiting podfile and license.json files. Because of some weird GitHub thing, the commit made by a CI cannot trigger another CI.

As I do not expect these commits to break the app, we can safely add a success comment in case the CI on the initial commit runs successfully.