@AfterClass
  public static void stopServices() throws Exception {
    if (miniHS2 != null && miniHS2.isStarted()) {
      miniHS2.stop();
    }
  }
Test that set/unset of metaconf:hive.metastore.disallow.incompatible.col.type.changes is local
to the session

Two connections are created.  In one connection
metaconf:hive.metastore.disallow.incompatible.col.type.changes is set to false.  Then the
columm type can changed from int to smallint.  In the other connection
metaconf:hive.metastore.disallow.incompatible.col.type.changes is left with the default value
true.  In that connection changing column type from int to smallint will throw an error.
itests/hive-unit/src/test/java/org/apache/hadoop/hive/metastore/TestHiveMetaStoreAlterColumnPar.java