ci: stop the secret scan reporting pytest names as Lob keys

The push that carried the whole branch through TruffleHog failed on a
"verified" Lob credential: `test_updates_an_existing_device_in_place`, a test
function in backend/tests/test_racks.py. Lob's detector matches any
`test_`-prefixed identifier of that length and reports it verified, because
Lob test-mode keys authenticate unconditionally — so verification proves
nothing here.

Lob is a direct-mail API this project does not use, and any pytest function
named that long trips it again, so the detector is excluded rather than the
test renamed.

ha-relevant: no

.github/workflows/security.yml

@@ -22,6 +22,12 @@ jobs:
         uses: trufflesecurity/trufflehog@main
         with:
           path: ./
+          # Lob (a direct-mail API this project does not use) matches any
+          # `test_`-prefixed identifier of ~35 chars and reports it verified,
+          # because Lob test keys authenticate unconditionally. Every pytest
+          # function named at that length trips it — the first was
+          # `test_updates_an_existing_device_in_place`.
+          extra_args: --exclude-detectors=Lob
 
   dependency-audit:
     runs-on: ubuntu-latest