chore(nodejs): Add system-test/fixtures to .eslintignore (#577)

* fix: Add `system-test/fixtures` to `.eslintignore`

* refactor: Use `**`

Source-Link: googleapis/synthtool@b7858ba
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest@sha256:abc68a9bbf4fa808b25fa16d3b11141059dc757dbc34f024744bba36c200b40f

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

.eslintignore

@@ -5,3 +5,4 @@ build/
 docs/
 protos/
 samples/generated/
+system-test/**/fixtures

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest
-  digest: sha256:e7a37871068ab50b3841cb08619c288dc0665b62a7f39f2bdb7dea0ce6e89a3d
-# created: 2023-09-22T19:12:26.585611364Z
+  digest: sha256:abc68a9bbf4fa808b25fa16d3b11141059dc757dbc34f024744bba36c200b40f
+# created: 2023-10-04T20:56:40.710775365Z