chore: add regex to match unmanaged dependency check (#1941) (#6499)

Source-Link: googleapis/synthtool@ca7a716
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-java:latest@sha256:cecae6152a85d55c932a64515643cf2e32a1f1b6e17503080eb07744b2177f28

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

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-java:latest
-  digest: sha256:81c3ec554428c8ff6c92f0d58668b7ef52265d053a82284c97a326745e786949
-# created: 2024-03-27T17:59:25.436353226Z
+  digest: sha256:cecae6152a85d55c932a64515643cf2e32a1f1b6e17503080eb07744b2177f28
+# created: 2024-03-25T17:31:37.187420732Z