feat: 🎸 add support for Angular v11.0.x (RC)

[NachoVazquez]

PR Checklist

Please check if your PR fulfills the following requirements:

• [ x ] The commit message follows our guidelines: CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• [ x ] Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[ x ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

There is no support for Angular v11-RC

Issue Number: N/A

What is the new behavior?

angular-versions-action supports v11-RC

Does this PR introduce a breaking change?

[ ] Yes
[ x ] No

Other information