ADD: use of issue-number on push when provided

[VincentAuriau]

Changes:
When issue-number is provided it is used over the commit sha to define where the comment is made.

Why?
Basically I have an issue tracking all the improvements in the development of the tests in a repository - let's say covering the whole code is a long term objective. I wanted the action to regularly update the issue with the latest coverage statistics

Also:

• I suppose it is a quiet uncommon objective and this behavior might be undesired, but still seemed logical to me not to ignore this input.
• I am not sure about the code changes since I never used javascript and just copied/paster what seemed logical
• I'd be happy to discuss the PR or improve the changes :)
• I'm not sure why the diff has so many lines, I juste added a few lines, maybe vscode did some weird stuff.

[MishaKav]

Can you please to include all your changes in "sec/index.js" file. Because the "dist" - is only the output for build command.

[VincentAuriau]

It's done !
I'm not sure how I managed to do it with dist directory but somehow it worked.
I've copied the changes in src/index.js, I suppose it needs to be checked and dist/ rebuilt...

Thank you !