Support running commands in repositories without action.yaml (#293)

* Comment for public function

* Add git describe fallback

* spelling: github

* Set initial branch to satisfy tests for modern git

* Clarify -even- if

* Go 1.16

* Support running commands in repositories without action.yaml

Support runnings commands with only a Docker file

Co-authored-by: Casey Lee <[email protected]>

pkg/common/git.go

@@ -189,6 +189,7 @@ type NewGitCloneExecutorInput struct {
 	Dir string
 }
 
+// CloneIfRequired ...
 func CloneIfRequired(refName plumbing.ReferenceName, input NewGitCloneExecutorInput, logger log.FieldLogger) (*git.Repository, error) {
 	r, err := git.PlainOpen(input.Dir)
 	if err != nil {