[GITEA] Use join for the deleting issue actions query

- The action tables can become very large as it's a dumpster for every
action that an user does on an repository.
- The following query: `DELETE FROM action WHERE comment_id IN (SELECT id FROM comment WHERE
issue_id=?)` is not using indexes for `comment_id` and is instead using
an full table scan by MariaDB.
- Rewriting the query to use an JOIN will allow MariaDB to use the
index.
- More information: https://codeberg.org/Codeberg-Infrastructure/techstack-support/issues/9

(cherry picked from commit 6646fcf31f)

Conflicts:
	tests/integration/api_nodeinfo_test.go
	https://codeberg.org/forgejo/forgejo/pulls/1178

models/activities/action_test.go

@@ -242,6 +242,15 @@ func TestGetFeedsCorrupted(t *testing.T) {
 	assert.Equal(t, int64(0), count)
 }
 
+func TestDeleteIssueActions(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	comment := unittest.AssertExistsAndLoadBean(t, &issue_model.Comment{ID: 8})
+	unittest.AssertExistsAndLoadBean(t, &activities_model.Action{ID: 10, CommentID: comment.ID})
+	assert.NoError(t, activities_model.DeleteIssueActions(db.DefaultContext, 32, 17))
+	unittest.AssertNotExistsBean(t, &activities_model.Action{ID: 10, CommentID: comment.ID})
+}
+
 func TestConsistencyUpdateAction(t *testing.T) {
 	if !setting.Database.Type.IsSQLite3() {
 		t.Skip("Test is only for SQLite database.")