Bump com.google.testing.compile:compile-testing from 0.18 to 0.21.0

Author: scordio

pom.xml

@@ -65,7 +65,7 @@
     <dependency>
       <groupId>com.google.testing.compile</groupId>
       <artifactId>compile-testing</artifactId>
-      <version>0.18</version>
+      <version>0.21.0</version>
       <scope>test</scope>
     </dependency>
     <dependency>