build: marking dependencies (8) non-required (#1472) (#798)

Co-authored-by: Anthonios Partheniou <partheniou@google.com>
Source-Link: googleapis/synthtool@72c64b7
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-java:latest@sha256:b2e8f445ca0e605d4bbefbfdbdf7335692d75cf1647af62243828dcc0ea4e690

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -14,4 +14,4 @@
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-java:latest
   digest: sha256:04f254abfe5f47fe73ae6f91d68d55c3b76e722a4943066c3bb0ce03573b4ad9
-# created: 2022-07-18T21:44:23.94208526Z
+# created: 2022-07-18T21:44:23.94208526Z