chore: run_context: add GITHUB_RUN_ATTEMPT (#2458) (#817)

* run_context: add GITHUB_RUN_ATTEMPT

Fixes nektos/act#2451
Fixes nektos/act#1615

* fix whitespace

* fix githubcontext

* fix TestSetupEnv

---------

Co-authored-by: ChristopherHX <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
(cherry picked from commit 4178166d289bae351ef6d33414cc569518e62a01)

```
Conflicts:
	act/runner/run_context.go
    trivial context conflict
	act/runner/step_test.go
    the corresponding test was removed in the Forgejo runner
```

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- other
  - [PR](https://code.forgejo.org/forgejo/runner/pulls/817): <!--number 817 --><!--line 0 --><!--description Y2hvcmU6IHJ1bl9jb250ZXh0OiBhZGQgR0lUSFVCX1JVTl9BVFRFTVBUICgjMjQ1OCk=-->chore: run_context: add GITHUB_RUN_ATTEMPT (#2458)<!--description-->
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Co-authored-by: Ryan <[email protected]>
Reviewed-on: https://code.forgejo.org/forgejo/runner/pulls/817
Reviewed-by: Michael Kriese <[email protected]>

Author: earl-warren

act/model/github_context.go

@@ -13,6 +13,7 @@ type GithubContext struct {
 	Event            map[string]interface{} `json:"event"`
 	EventPath        string                 `json:"event_path"`
 	Workflow         string                 `json:"workflow"`
+	RunAttempt       string                 `json:"run_attempt"`
 	RunID            string                 `json:"run_id"`
 	RunNumber        string                 `json:"run_number"`
 	Actor            string                 `json:"actor"`

act/runner/run_context.go

@@ -1108,6 +1108,7 @@ func (rc *RunContext) getGithubContext(ctx context.Context) *model.GithubContext
 	ghc := &model.GithubContext{
 		Event:            make(map[string]interface{}),
 		Workflow:         rc.Run.Workflow.Name,
+		RunAttempt:       rc.Config.Env["GITHUB_RUN_ATTEMPT"],
 		RunID:            rc.Config.Env["GITHUB_RUN_ID"],
 		RunNumber:        rc.Config.Env["GITHUB_RUN_NUMBER"],
 		Actor:            rc.Config.Actor,
@@ -1136,6 +1137,10 @@ func (rc *RunContext) getGithubContext(ctx context.Context) *model.GithubContext
 		ghc.Workspace = rc.JobContainer.ToContainerPath(rc.Config.Workdir)
 	}
 
+	if ghc.RunAttempt == "" {
+		ghc.RunAttempt = "1"
+	}
+
 	if ghc.RunID == "" {
 		ghc.RunID = "1"
 	}
@@ -1294,6 +1299,7 @@ func (rc *RunContext) withGithubEnv(ctx context.Context, github *model.GithubCon
 	}
 	env["CI"] = "true"
 	set("WORKFLOW", github.Workflow)
+	set("RUN_ATTEMPT", github.RunAttempt)
 	set("RUN_ID", github.RunID)
 	set("RUN_NUMBER", github.RunNumber)
 	set("ACTION", github.Action)