`%` in regex condition breaks segment count refresh

[sentry]

Sentry Issue: FLAGSMITH-API-684

TypeError: not enough arguments for format string
(5 additional frame(s) were not displayed)
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  File "segment_membership/tasks.py", line 222, in refresh_project_segment_counts
    membership_counts = compute_segment_counts_for_project(project, cursor)
  File "segment_membership/services.py", line 141, in compute_segment_counts_for_project
    cursor.execute(sql, {"env_keys": tuple(env_id_by_key)})

{'project__id': 10908, 'event': 'refresh.project.failed', 'logger': 'segment_membership', 'level': 'error', 'exception': 'Traceback (most recent call last):\n  File "/app/segment_membership/tasks.py", line 222, in refresh_project_segment_counts\n    membership_counts = compute_segment_counts_for_project(project, cursor)\n  File "/app/segment_membership/services.py", line 141, in compute_segment_counts_for_project\n    cursor.execute(sql, {"env_keys": tuple(env_id_by_key)})\n    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File "/build/.venv/lib/python3.13/site-packages/sentry_sdk/utils.py", line 1841, in runner\n    return sentry_patched_function(*args, **kwargs)\n  File "/build/.venv/lib/python3.13/site-packages/sentry_sdk/integrations/django/__init__.py", line 645, in execute\n    result = real_execute(self, sql, params)\n  File "/build/.venv/lib/python3.13/site-packages/django/db/backends/utils.py", line 79, in execute\n    return self._execute_with_wrappers(\n           ~~~~~~~~~~~~~~~~~~~~~~~~~~~^\n        sql, params, many=False, executor=self._execute\n        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n    )\n    ^\n  File "/build/.venv/lib/python3.13/site-packages/django/db/backends/utils.py", line 92, in _execute_with_wrappers\n    return executor(sql, params, many, context)\n  File "/build/.venv/lib/python3.13/site-packages/django/db/backends/utils.py", line 105, in _execute\n    return self.cursor.execute(sql, params)\n           ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^\n  File "/build/.venv/lib/python3.13/site-packages/clickhouse_backend/driver/connection.py", line 171, in execute\n    super().execute(operation, parameters)\n    ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^\n  File "/build/.venv/lib/python3.13/site-packages/clickhouse_driver/dbapi/cursor.py", line 111, in execute\n    response = execute(\n        operation, params=parameters, with_column_types=True,\n        **execute_kwargs\n    )\n  File "/build/.venv/lib/python3.13/site-packages/clickhouse_backend/driver/client.py", line 53, in execute\n    rv = self.process_ordinary_query(\n        query,\n    ...<5 lines>...\n        columnar=columnar,\n    )\n  File "/build/.venv/lib/python3.13/site-packages/clickhouse_driver/client.py", line 574, in process_ordinary_query\n    query = self.substitute_params(\n        query, params, self.connection.context\n    )\n  File "/build/.venv/lib/python3.13/site-packages/clickhouse_backend/driver/client.py", line 24, in substitute_params\n    return query % escaped\n           ~~~~~~^~~~~~~~~\nTypeError: not enough arguments for format string', 'timestamp': '2026-07-02T11:33:12.132814Z'}