Have Apiary clients sorted as third party by ruff (LIB-93) (#46)

Co-authored-by: graphite-app[bot] <96075541+graphite-app[bot]@users.noreply.github.com>

Author: jzink-duo

ruff.toml

@@ -8,6 +8,9 @@ convention = "pep257"
 
 [isort]
 combine-as-imports = true
+# We force Apiary generated clients to be sorted as external libraries to prevent
+# thrashing between local and CI environments.
+known-third-party = ["*_backend_client"]
 
 [lint]
 ignore = [