revset: remove the last usage of "%d" for a non-revision entry

In order to fix an important bug, we are about to narrow the semantic of "%d"
in revset. This is one of the few exceptions that we need to get rid of before
being able to fix the bug.

See the later semantic narrowing changeset for full rationale on the semantic
change.

mercurial/exchangev2.py

@@ -98,7 +98,7 b' def pull(pullop):'
         relevantcsetnodes = set()
         clnode = repo.changelog.node
 
-        for rev in repo.revs(b'ancestors(%ln, %d)',
+        for rev in repo.revs(b'ancestors(%ln, %s)',
                              pullheads, pullop.depth - 1):
             relevantcsetnodes.add(clnode(rev))