Revert "Update mysql-connector-java to 6.0.6"

This reverts commit 051ca83af772401af317e2e84053c71a5b7527ea.

Updating to mysql-connector-java 6.0.6 broke the sql upgrader in Gerrit.

Bug: Issue 7331
Change-Id: Id6dc6c93b6f989b096114a35c84cb4febae07613
diff --git a/pom.xml b/pom.xml
index 0babde9..78aaf8b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -518,7 +518,7 @@
     <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
-      <version>6.0.6</version>
+      <version>5.1.41</version>
       <scope>test</scope>
     </dependency>
 
diff --git a/src/test/java/com/google/gwtorm/schema/sql/DialectMySQLTest.java b/src/test/java/com/google/gwtorm/schema/sql/DialectMySQLTest.java
index de75464..8789122 100644
--- a/src/test/java/com/google/gwtorm/schema/sql/DialectMySQLTest.java
+++ b/src/test/java/com/google/gwtorm/schema/sql/DialectMySQLTest.java
@@ -57,7 +57,7 @@
     dialect = new DialectMySQL().refine(db);
 
     final Properties p = new Properties();
-    p.setProperty("driver", com.mysql.cj.jdbc.Driver.class.getName());
+    p.setProperty("driver", com.mysql.jdbc.Driver.class.getName());
     p.setProperty("url", db.getMetaData().getURL());
     p.setProperty("user", user);
     p.setProperty("password", pass);