deps: update dependency io.grafeas:grafeas to v2.0.6 (#724)

Author: renovate-bot

pom.xml

@@ -96,7 +96,7 @@
       <dependency>
         <groupId>io.grafeas</groupId>
         <artifactId>grafeas</artifactId>
-        <version>2.0.5</version>
+        <version>2.0.6</version>
       </dependency>
       <!-- TODO: Until gax-grpc && grafeas align  -->