./prepare-release.sh script does not take into account the changed CHANGLOG.md files

[agatsoh]

Description

In the RELEASE.md document here first CHANGELOG files from all the 3 repos are changed but when
./prepare-release.sh script is executed it makes a commit only from the files it changed(all the package.json files) ignoring any other files. But all the files needed for the commit should ideally come in one commit.

Acceptance criteria

• Hence it would be nice if ./prepare-release.sh script takes into account all the CHANGELOG files from each of the repository's and makes a commit.

Tasks

• Take into account CHANGELOG files while making a commit.