Merge pull request 'fix: Do not fail on nil error' (#87) from vpotyarkin/act:fix/nil-error into main

Reviewed-on: https://code.forgejo.org/forgejo/act/pulls/87
Reviewed-by: Michael Kriese <michael.kriese@gmx.de>

act/container/docker_run.go

@@ -753,7 +753,7 @@ func (cr *containerReference) copyDir(dstPath string, srcPath string, useGitIgno
 		defer func(tarFile *os.File) {
 			name := tarFile.Name()
 			err := tarFile.Close()
-			if !errors.Is(err, os.ErrClosed) {
+			if err != nil && !errors.Is(err, os.ErrClosed) {
 				logger.Error(err)
 			}
 			err = os.Remove(name)