Workflow run's attempt number not available in context

[HW13]

Describe the enhancement Add workflow run's attempt number to context

Code Snippet The code has been implemented in #1387

Additional information Since it's a pretty small change, I went ahead and opened a PR - hope that's ok 😅

[corneliusroemer]

Would also like to have this - because only on the first attempt do I need to wait for a deployment to finish.

[javiplx]

No idea when was done, but the github.run_attempt is already there

[bbrzoska]

can we get this one merged plz?