run_tests: only allow help2man skipping in CI

Make sure we run this for local devs.

Change-Id: I472b7c347086d54649dd9d5778eea4737447b353
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/471921
Tested-by: Mike Frysinger <[email protected]>
Reviewed-by: Scott Lee <[email protected]>
Commit-Queue: Mike Frysinger <[email protected]>

Author: vapier

run_tests

@@ -104,7 +104,8 @@ def run_isort():
 
 def run_update_manpages() -> int:
     """Returns the exit code from release/update-manpages."""
-    if not shutil.which("help2mafn"):
+    # Allow this to fail on CI, but not local devs.
+    if is_ci() and not shutil.which("help2man"):
         print("update-manpages: help2man not found; skipping test")
         return 0