Add release workflow

[ekohl]

This workflow automatically releases new tags starting with v.

[ekohl]

I wonder where this came from:

/opt/hostedtoolcache/Ruby/2.7.8/x64/lib/ruby/2.7.0/rubygems.rb:277:in
`find_spec_for_exe': can't find gem rake (>= 0.a) with executable rake
(Gem::GemNotFoundException)

Something depends on rake without declaring it as a dependency? It's not quite clear to me where it exactly comes from.

[evgeni]

It tries to pull the Google SDK and that needs Rake to build iself. 🤯

[ekohl]

This won't work because MFA is required:

foreman_google/foreman_google.gemspec

Line 7 in 5561307

'rubygems_mfa_required' => 'true' }