[Java] Upgrade to Checkstyle 8.25.

Author: mjpt777

build.gradle

@@ -126,7 +126,7 @@ subprojects {
     jar.enabled = true
 
     dependencies {
-        checkstyle 'com.puppycrawl.tools:checkstyle:8.24'
+        checkstyle 'com.puppycrawl.tools:checkstyle:8.25'
 
         compile 'org.agrona:agrona:1.0.8'
 
@@ -135,7 +135,7 @@ subprojects {
         testCompile 'junit:junit:4.12'
     }
 
-    checkstyle.toolVersion = '8.24'
+    checkstyle.toolVersion = '8.25'
 
     compileJava {
         sourceCompatibility = sbeJavaVersion