Correctly handle moved files in apply patch (#22118) (#22135)

Backport #22118

Moved files in a patch will result in git apply returning:

```
error: {filename}: No such file or directory
```

This wasn't handled by the git apply patch code. This PR adds handling
for this.

Fix #22083

Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

services/pull/patch.go

@@ -53,6 +53,8 @@ var patchErrorSuffices = []string{
 	": patch does not apply",
 	": already exists in working directory",
 	"unrecognized input",
+	": No such file or directory",
+	": does not exist in index",
 }
 
 // TestPatch will test whether a simple patch will apply
@@ -416,6 +418,7 @@ func checkConflicts(ctx context.Context, pr *issues_model.PullRequest, gitRepo *
 				scanner := bufio.NewScanner(stderrReader)
 				for scanner.Scan() {
 					line := scanner.Text()
+					log.Trace("PullRequest[%d].testPatch: stderr: %s", pr.ID, line)
 					if strings.HasPrefix(line, prefix) {
 						conflict = true
 						filepath := strings.TrimSpace(strings.Split(line[len(prefix):], ":")[0])