refactor: a helper for paged results

"When using a paged API endpoint, I want an iterable of pages" -- No one ever.

This helper lets us focus on the things we care about: the items we are
asking for.

edx_repo_tools/repo_checks/repo_checks.py

@@ -43,6 +43,13 @@
 cache = lru_cache(maxsize=None)
 
 
+def all_paged_items(func, *args, **kwargs):
+    """
+    Get all items from a GhApi function returning paged results.
+    """
+    return chain.from_iterable(paged(func, *args, per_page=100, **kwargs))
+
+
 def is_security_private_fork(api, org, repo):
     """
     Check to see if a specific repo is a private security fork.
@@ -373,14 +380,11 @@ def fix(self, dry_run=False):
                 )
 
         # Check to see if a PR exists
-        prs = chain.from_iterable(
-            paged(
-                self.api.pulls.list,
-                owner=self.org_name,
-                repo=self.repo_name,
-                head=self.branch_name,
-                per_page=100,
-            )
+        prs = all_paged_items(
+            self.api.pulls.list,
+            owner=self.org_name,
+            repo=self.repo_name,
+            head=self.branch_name,
         )
 
         prs = [pr for pr in prs if pr.head.ref == self.branch_name]
@@ -438,13 +442,10 @@ def check(self):
         """
         See if our labels exist.
         """
-        existing_labels_from_api = chain.from_iterable(
-            paged(
-                self.api.issues.list_labels_for_repo,
-                self.org_name,
-                self.repo_name,
-                per_page=100,
-            )
+        existing_labels_from_api = all_paged_items(
+            self.api.issues.list_labels_for_repo,
+            self.org_name,
+            self.repo_name,
         )
         existing_labels = {
             self._simplify_label(label.name): {
@@ -555,13 +556,10 @@ def is_relevant(self):
         raise NotImplementedError
 
     def check(self):
-        teams = chain.from_iterable(
-            paged(
-                self.api.repos.list_teams,
-                self.org_name,
-                self.repo_name,
-                per_page=100,
-            )
+        teams = all_paged_items(
+            self.api.repos.list_teams,
+            self.org_name,
+            self.repo_name,
         )
 
         team_permissions = {team.slug: team.permission for team in teams}
@@ -943,14 +941,11 @@ def main(org, dry_run, _github_token, check_names, repos, start_at):
     if not repos:
         repos = [
             repo.name
-            for repo in chain.from_iterable(
-                paged(
-                    api.repos.list_for_org,
-                    org,
-                    sort="created",
-                    direction="desc",
-                    per_page=100,
-                )
+            for repo in all_paged_items(
+                api.repos.list_for_org,
+                org,
+                sort="created",
+                direction="desc",
             )
         ]