AVRO-1833: Java: Add test dependency for guava.

This was caught by running the tests via build.sh in docker for the
release build.
diff --git a/lang/java/compiler/pom.xml b/lang/java/compiler/pom.xml
index 678ccf8..3ff0101 100644
--- a/lang/java/compiler/pom.xml
+++ b/lang/java/compiler/pom.xml
@@ -133,6 +133,18 @@
       <groupId>joda-time</groupId>
       <artifactId>joda-time</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava</artifactId>
+      <version>${guava.version}</version>
+      <scope>test</scope>
+      <exclusions>
+        <exclusion> <!-- GPL -->
+          <groupId>com.google.code.findbugs</groupId>
+          <artifactId>jsr305</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
   </dependencies>
 
 </project>