Fix branch commit message too long problem (#25588)

When branch's commit CommitMessage is too long, the column maybe too
short.(TEXT 16K for mysql).
This PR will fix it to only store the summary because these message will
only show on branch list or possible future search?

models/git/branch_test.go

@@ -11,6 +11,7 @@ import (
 	issues_model "code.gitea.io/gitea/models/issues"
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/util"
 
 	"github.com/stretchr/testify/assert"
@@ -28,7 +29,15 @@ func TestAddDeletedBranch(t *testing.T) {
 	secondBranch := unittest.AssertExistsAndLoadBean(t, &git_model.Branch{RepoID: repo.ID, Name: "branch2"})
 	assert.True(t, secondBranch.IsDeleted)
 
-	err := git_model.UpdateBranch(db.DefaultContext, repo.ID, secondBranch.Name, secondBranch.CommitID, secondBranch.CommitMessage, secondBranch.PusherID, secondBranch.CommitTime.AsLocalTime())
+	commit := &git.Commit{
+		ID:            git.MustIDFromString(secondBranch.CommitID),
+		CommitMessage: secondBranch.CommitMessage,
+		Committer: &git.Signature{
+			When: secondBranch.CommitTime.AsLocalTime(),
+		},
+	}
+
+	err := git_model.UpdateBranch(db.DefaultContext, repo.ID, secondBranch.PusherID, secondBranch.Name, commit)
 	assert.NoError(t, err)
 }