Fix total pages not being on any return call.

gitlab_api/gitlab_api.py

@@ -1481,7 +1481,7 @@ def get_merge_requests(self, **kwargs) -> Union[Response, requests.Response]:
                 headers=self.headers,
                 verify=self.verify,
             )
-            total_pages = int(response.headers["X-Total-Pages"])
+            total_pages = int(response.headers.get("X-Total-Pages", 1))
             response = []
             if merge_request.max_pages == 0 or merge_request.max_pages > total_pages:
                 merge_request.max_pages = total_pages
@@ -2174,7 +2174,7 @@ def get_nested_projects_by_group(
             pages_response = self.get_total_projects_in_group(
                 group_id=project.group_id, per_page=project.per_page
             )
-            total_pages = int(pages_response.headers["X-Total-Pages"])
+            total_pages = int(pages_response.headers.get("X-Total-Pages", 1))
             if (
                 not project.max_pages
                 or project.max_pages == 0

gitlab_api/gitlab_models.py

@@ -3413,9 +3413,7 @@ class Meta:
     billable_members_count: Optional[int] = Field(
         default=None, description="The Billable members count of the namespace, if any."
     )
-    plan: Optional[str] = Field(
-        default=None, description="Plan of the Namespace"
-    )
+    plan: Optional[str] = Field(default=None, description="Plan of the Namespace")
     trial_ends_on: Optional[datetime] = Field(
         default=None, description="The date the Trial ends"
     )