[KYUUBI #1306] Rename EventLoggerType DB to JDBC

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### _Why are the changes needed?_
Fix #1306

### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [ ] Add screenshots for manual tests if appropriate

- [ ] [Run test](https://kyuubi.readthedocs.io/en/latest/develop_tools/testing.html#running-tests) locally before make a pull request

Closes #1309 from jiaoqingbo/kyuubi1.

Closes #1306

e0e5ce6c [jiaoqingbo] [KYUUBI #1306] Set DB to JDBC

Authored-by: jiaoqingbo <1178404354@qq.com>
Signed-off-by: Cheng Pan <chengpan@apache.org>

kyuubi-common/src/main/scala/org/apache/kyuubi/events/EventLoggerType.scala

@@ -22,5 +22,5 @@ object EventLoggerType extends Enumeration {
   type EventLoggerType = Value
 
   // TODO: Only SPARK is done now
-  val SPARK, JSON, DB, CUSTOM = Value
+  val SPARK, JSON, JDBC, CUSTOM = Value
 }