Correct wrong datetime format for git (#7689)

modules/git/repo_tree.go

@@ -61,7 +61,7 @@ type CommitTreeOpts struct {
 
 // CommitTree creates a commit from a given tree id for the user with provided message
 func (repo *Repository) CommitTree(sig *Signature, tree *Tree, opts CommitTreeOpts) (SHA1, error) {
-	commitTimeStr := time.Now().Format(time.UnixDate)
+	commitTimeStr := time.Now().Format(time.RFC3339)
 
 	// Because this may call hooks we should pass in the environment
 	env := append(os.Environ(),

modules/repofiles/temp_repo.go

@@ -249,7 +249,7 @@ func (t *TemporaryUploadRepository) GetLastCommitByRef(ref string) (string, erro
 
 // CommitTree creates a commit from a given tree for the user with provided message
 func (t *TemporaryUploadRepository) CommitTree(author, committer *models.User, treeHash string, message string) (string, error) {
-	commitTimeStr := time.Now().Format(time.UnixDate)
+	commitTimeStr := time.Now().Format(time.RFC3339)
 	authorSig := author.NewGitSig()
 	committerSig := committer.NewGitSig()