[FEAT] Rename github repository to github-actions

[ronnetzer]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  
[ ] Performance issue
[x] Feature request
[ ] Documentation issue or request
[ ] Support request
[ ] Other... Please describe:

Current behavior

currently the repo implies to have only nx related actions

Expected behavior

in #45 we'll introduce new actions that are not related to nx so the name of the repo should reflect that.
As each action is published in its own repo, it shouldn't affect the consumers, only contributors will be affected by this.