docs(import[gitlab]) Fix misleading pagination metadata comment

why: The comment "Capture pagination metadata from first page" was
misleading because x-next-page is updated on every page, not just
the first. Only x-total is captured from the first response.

what:
- Change comment to "Capture x-total from first response" at both
  locations (_fetch_search and _paginate_repos)

Author: tony

src/vcspull/_internal/remotes/gitlab.py

@@ -213,7 +213,7 @@ def _fetch_search(self, options: ImportOptions) -> t.Iterator[RemoteRepo]:
 
             self._log_rate_limit(headers)
 
-            # Capture pagination metadata from first page
+            # Capture x-total from first response
             if page == 1:
                 x_total = headers.get("x-total")
                 if x_total is not None:
@@ -296,7 +296,7 @@ def _paginate_repos(
 
             self._log_rate_limit(headers)
 
-            # Capture pagination metadata from first page
+            # Capture x-total from first response
             if page == 1:
                 x_total = headers.get("x-total")
                 if x_total is not None: