Check commit message hashes before making links (#7713)

* Check commit message hashes before making links

Previously, when formatting commit messages, anything
that looked like SHA1 hashes was turned into a link
using regex. This meant that certain phrases or numbers
such as `777777` or `deadbeef` could be recognized as a commit
even if the repository has no commit with those hashes.

This change will make it so that anything that looks
like a SHA1 hash using regex will then also be checked
to ensure that there is a commit in the repository
with that hash before making a link.

Signed-off-by: Gary Kim <gary@garykim.dev>

* Use gogit to check if commit exists

This commit modifies the commit hash check
in the render for commit messages to use
gogit for better performance.

Signed-off-by: Gary Kim <gary@garykim.dev>

* Make code cleaner

Signed-off-by: Gary Kim <gary@garykim.dev>

* Use rev-parse to check if commit exists

Signed-off-by: Gary Kim <gary@garykim.dev>

* Add and modify tests for checking hashes in html link rendering

Signed-off-by: Gary Kim <gary@garykim.dev>

* Return error in sha1CurrentPatternProcessor

Co-Authored-By: mrsdizzie <info@mrsdizzie.com>

* Import Gitea log module

Signed-off-by: Gary Kim <gary@garykim.dev>

* Revert "Return error in sha1CurrentPatternProcessor"

This reverts commit 28f561cac46ef7e51aa26aefcbe9aca4671366a6.

Signed-off-by: Gary Kim <gary@garykim.dev>

* Add debug logging to sha1CurrentPatternProcessor

This will log errors by the git command run in
sha1CurrentPatternProcessor if the error is one
that was unexpected.

Signed-off-by: Gary Kim <gary@garykim.dev>

modules/markup/markdown/markdown_test.go

@@ -21,8 +21,9 @@ const AppSubURL = AppURL + Repo + "/"
 
 // these values should match the Repo const above
 var localMetas = map[string]string{
-	"user": "gogits",
-	"repo": "gogs",
+	"user":     "gogits",
+	"repo":     "gogs",
+	"repoPath": "../../../integrations/gitea-repositories-meta/user13/repo11.git/",
 }
 
 func TestRender_StandardLinks(t *testing.T) {
@@ -103,7 +104,7 @@ func testAnswers(baseURLContent, baseURLImages string) []string {
 <li><a href="` + baseURLContent + `/Tips" rel="nofollow">Tips</a></li>
 </ul>
 
-<p>See commit <a href="http://localhost:3000/gogits/gogs/commit/fc7f44dadf" rel="nofollow"><code>fc7f44dadf</code></a></p>
+<p>See commit <a href="http://localhost:3000/gogits/gogs/commit/65f1bf27bc" rel="nofollow"><code>65f1bf27bc</code></a></p>
 
 <p>Ideas and codes</p>
 
@@ -194,7 +195,7 @@ var sameCases = []string{
 - [[Links, Language bindings, Engine bindings|Links]]
 - [[Tips]]
 
-See commit fc7f44dadf
+See commit 65f1bf27bc
 
 Ideas and codes