tests: Fix update-manpages test.

Change-Id: I58d85e06edeb9208a782957acc982e996c026ed2
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/351854
Reviewed-by: Sam Saccone <samccone@google.com>
Tested-by: LaMont Jones <lamontjones@google.com>
diff --git a/tests/update_manpages.py b/tests/update_manpages.py
index 40bbdea..e89c5d8 120000
--- a/tests/update_manpages.py
+++ b/tests/update_manpages.py
@@ -1 +1 @@
-update-manpages
\ No newline at end of file
+../release/update-manpages
\ No newline at end of file