Defer one foreign key (#3239)

This is the only non-deferred foreign key actually used. We might as
well defer it because we defer all the others, and it's only due to luck
that we haven't hit errors due to this.

Also fix the generation script to remove unnecessary and breaking
restrict/unrestrict lines.

config/nom_build.py

@@ -19,7 +19,7 @@ import argparse
 import dataclasses
 import io
 import os
-import shutil
+import re
 import subprocess
 import sys
 from typing import List, Union
@@ -285,11 +285,17 @@ def do_pseudo_task(task: str) -> None:
         print('\033[33mWARNING:\033[0m Ignore the above failure, it is '
               'expected.')
 
-        # Copy the new schema into place.
-        shutil.copy(f'{root}/db/build/resources/test/testcontainer/'
-                    'mount/dump.txt',
-                    f'{root}/db/src/main/resources/sql/schema/'
-                    'nomulus.golden.sql')
+        # Copy the new schema into place, stripping psql \restrict and
+        # \unrestrict meta-commands emitted by pg_dump 17.6+.
+        dump_path = (f'{root}/db/build/resources/test/testcontainer/'
+                     'mount/dump.txt')
+        golden_path = (f'{root}/db/src/main/resources/sql/schema/'
+                       'nomulus.golden.sql')
+        with open(dump_path, 'r', encoding='utf-8') as src:
+            content = re.sub(
+                r'^\\(un)?restrict .*\n\n?', '', src.read(), flags=re.MULTILINE)
+        with open(golden_path, 'w', encoding='utf-8') as dst:
+            dst.write(content)
 
         # Rerun :db:test and regenerate the ER diagram (at "warning" log
         # level so it doesn't generate pages of messaging)