POM: Remove Google Java Format version specifier.

Change-Id: Iae9d0be8684a2420cf873f158fa4f5d9d7b66295
diff --git a/jgvariant-parent/pom.xml b/jgvariant-parent/pom.xml
index 4a2c2f2..4d053fc 100644
--- a/jgvariant-parent/pom.xml
+++ b/jgvariant-parent/pom.xml
@@ -72,7 +72,6 @@
 
     <apiguardian.version>1.1.2</apiguardian.version>
     <errorprone.version>2.23.0</errorprone.version>
-    <google-java-format.version>1.15.0</google-java-format.version>
     <guava.version>32.1.3-jre</guava.version>
     <inject-resources.version>0.3.3</inject-resources.version>
     <jetbrains-annotations.version>24.1.0</jetbrains-annotations.version>
@@ -295,7 +294,6 @@
               <order>java,javax,org,com,de,io,dagger,eu.mulk,</order>
             </importOrder>
             <googleJavaFormat>
-              <version>${google-java-format.version}</version>
               <style>GOOGLE</style>
             </googleJavaFormat>
           </java>