build(node): update client library version in samples metadata (#1356) (#197)

* build(node): add feat in node post-processor to add client library version number in snippet metadata

Co-authored-by: Benjamin E. Coe <bencoe@google.com>
Source-Link: googleapis/synthtool@d337b88
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest@sha256:d106724ad2a96daa1b8d88de101ba50bdb30b8df62ffa0aa2b451d93b4556641

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-nodejs:latest
-  digest: sha256:80bfa0c67226453b37b501be7748b2fa2a2676cfeec0012e79e3a1a8f1cbe6a3
-# created: 2022-04-14T19:57:08.518420247Z
+  digest: sha256:d106724ad2a96daa1b8d88de101ba50bdb30b8df62ffa0aa2b451d93b4556641
+# created: 2022-04-20T16:59:29.058398639Z