### What changes were proposed in this pull request?
This PR updates JDBC Integration Test DBMS Docker Images.
| DBMS | Docker Image Tag | Release |
| ------ | ------------------ | ------ |
| MySQL | mysql:5.7.28 | Oct 13, 2019 |
| PostgreSQL | postgres:12.0-alpine | Oct 3, 2019 |
* For `MySQL`, `SET GLOBAL sql_mode = ''` is added to disable all strict modes because `test("Basic write test")` creates a table like the following. The latest MySQL rejects `0000-00-00 00:00:00` as TIMESTAMP and causes the test case failure.
```
mysql> desc datescopy;
+-------+-----------+------+-----+---------------------+-----------------------------+
| Field | Type | Null | Key | Default | Extra |
+-------+-----------+------+-----+---------------------+-----------------------------+
| d | date | YES | | NULL | |
| t | timestamp | NO | | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| dt | timestamp | NO | | 0000-00-00 00:00:00 | |
| ts | timestamp | NO | | 0000-00-00 00:00:00 | |
| yr | date | YES | | NULL | |
+-------+-----------+------+-----+---------------------+-----------------------------+
```
* For `PostgreSQL`, I chose the smallest image in `12` releases. It reduces the image size a lot, `312MB` -> `72.8MB`. This is good for CI/CI testing environment.
```
$ docker images | grep postgres
postgres 12.0-alpine 5b681acb1cfc 2 days ago 72.8MB
postgres 11.4 53912975086f 3 months ago 312MB
```
Note that
- For `MsSqlServer`, we are using `2017-GA-ubuntu` and the next version `2019-CTP3.2-ubuntu` is still `Community Technology Preview` status.
- For `DB2` and `Oracle`, the official images are not available.
### Why are the changes needed?
This is to make it sure we are testing with the latest DBMS images during preparing `3.0.0`.
### Does this PR introduce any user-facing change?
No.
### How was this patch tested?
Since this is the integration test, we need to run this manually.
```
build/mvn install -DskipTests
build/mvn -Pdocker-integration-tests -pl :spark-docker-integration-tests_2.12 test
```
Closes#26224 from dongjoon-hyun/SPARK-29567.
Authored-by: Dongjoon Hyun <dhyun@apple.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
7ecf968527