build(deps): update dependency org.apache.maven.plugins:maven-compiler-plugin to v3.12.1 (#2379)

Author: renovate-bot

gapic-generator-java/pom.xml

@@ -106,7 +106,7 @@
       </plugin>
       <plugin>
         <artifactId>maven-compiler-plugin</artifactId>
-        <version>3.11.0</version>
+        <version>3.12.1</version>
         <configuration>
           <source>8</source>
           <target>8</target>