[KYUUBI #2532] avoid NPE in KyuubiHiveDriver.acceptsURL

### _Why are the changes needed?_

avoid NPE in KyuubiHiveDriver.acceptsURL

### _How was this patch tested?_

- [x] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [x] Add screenshots for manual tests if appropriate

- [x] [Run test](https://kyuubi.apache.org/docs/latest/develop_tools/testing.html#running-tests) locally before make a pull request

Closes #2532 from gabrywu/avoidNPE.

Closes #2532

16096e1 [gabrywu] avoid NPE in KyuubiHiveDriver.acceptsURL

Authored-by: gabrywu <gabrywu@apache.org>
Signed-off-by: Cheng Pan <chengpan@apache.org>

Author: gabry-lab

kyuubi-hive-jdbc/src/main/java/org/apache/kyuubi/jdbc/KyuubiHiveDriver.java

@@ -48,7 +48,7 @@ public class KyuubiHiveDriver implements Driver {
 
   @Override
   public boolean acceptsURL(String url) throws SQLException {
-    return url.startsWith(Utils.URL_PREFIX);
+    return url != null && url.startsWith(Utils.URL_PREFIX);
   }
 
   @Override