Keep the two tests that fail on main without the fix:
- test_fal_common: a keyed managed submit makes exactly one POST (plus the
negative arm: an unkeyed submit still goes through the SDK retry ladder)
- test_image_generation: the 409 BILLING_ERROR body surfaces
`unsupported_pricing_meter` instead of the generic "not yet enabled" text
Dropped from #106484: the duplicate video-plugin billing test (same helper,
same assertion), the `_fal_client = fake` / `import_fal_client` stub churn
and the `tools.lazy_deps` stub — fal-client is installed in CI (`--extra fal`)
so those fixtures were not needed; the `_load_fal_client` no-op fixture on
TestManagedGatewayErrorTranslation for the same reason.
Also drop the redundant `retry_request is None` re-check in
`_ManagedFalSyncClient.submit` — `__init__` already raises when the helper
is missing.
acf9177c70