Add GitHub action workflow to validate changelog

[utsav-pal]

Hi I tried to add a new GitHub Actions workflow to validate changelog entries in pull requests.

I tested locally on my fork repo by making a PR from branch test-for-changelog.yaml to branch Github-Action ones , then this time is failed the valid check but when I add the label skip-changelog it passes the all the check

Fixes #555

How to use

• All PRs will automatically be checked for changelog entries
• To skip the check for PRs that don't need changelog entries (docs, CI changes, etc.), add the skip-changelog label

[kailan]

This looks good to me! I made one small change to use ubuntu-latest in line with the other workflows in this repository.

Thank you for your contribution :)

[kailan]

hah, the check failed. obviously.