use constant instead of literal string

mktip · Mohammad Kefah · commit 4b689826bfc1 · 2019-06-11T02:41:16.000+03:00
Signed-off-by: Mohammad Kefah &lt;mo@edraj.io&gt;
diff --git a/worktree.go b/worktree.go
@@ -722,7 +722,7 @@ func (w *Worktree) Clean(opts *CleanOptions) error {
 
 func (w *Worktree) doClean(status Status, opts *CleanOptions, dir string, files []os.FileInfo) error {
 	for _, fi := range files {
-		if fi.Name() == ".git" {
+		if fi.Name() == GitDirName {
 			continue
 		}
 

Original file line number	Diff line number	Diff line change
`@@ -722,7 +722,7 @@ func (w Worktree) Clean(opts CleanOptions) error {`
`722`	`722`
`723`	`723`	`func (w Worktree) doClean(status Status, opts CleanOptions, dir string, files []os.FileInfo) error {`
`724`	`724`	`for _, fi := range files {`
`725`		`- if fi.Name() == ".git" {`
	`725`	`+ if fi.Name() == GitDirName {`
`726`	`726`	`continue`
`727`	`727`	`}`
`728`	`728`