fix: use configured GitLab URL instead of hardcoded gitlab.com

The previous pagination implementation accidentally hardcoded the GitLab URL
to gitlab.com, breaking the integration for self-hosted GitLab instances.

Changes:
- Replace hardcoded 'https://gitlab.com' with gitlabProvider.gitlabUrl
- Maintains the pagination functionality added in previous commit

Fixes: GitLab branches API calls failing for self-hosted instances

packages/server/src/utils/providers/gitlab.ts

@@ -316,7 +316,7 @@ export const getGitlabBranches = async (input: {
 
 	while (true) {
 		const branchesResponse = await fetch(
-			`https://gitlab.com/api/v4/projects/${input.id}/repository/branches?page=${page}&per_page=${perPage}`,
+			`${gitlabProvider.gitlabUrl}/api/v4/projects/${input.id}/repository/branches?page=${page}&per_page=${perPage}`,
 			{
 				headers: {
 					Authorization: `Bearer ${gitlabProvider.accessToken}`,