Add support for building the cli on pull request

## Why you need it?
To build the cli when someone contributes a PR and it is accepted.

## How it could be?
A "contrib" workflow in github.com/apache/openserverless-cli that
- createa a tag from the version.txt
- trigger a build and a release using the release workflow

## Other related information
A partial implementation creating the tag when someone contribute a PR is already available.
However looks like it does not trigger another build for some reasons.
We shoulud either add the trigger or merge the code with the release workflow so it is activated both by pr AND pull requests.