Flink: Run unit tests for different versions.

[openinx]

I think this PR: #3364 forgot to run the common flink unit tests for the given specific flink version. So when I run the following command , it even did not run any test cases.

./gradlew  -DflinkVersions=1.13 :iceberg-flink:iceberg-flink-1.13:build -Pquick=true -x javadoc

This RP is trying to enable the unit tests check for different flink versions.

[openinx]

I found this because:

1. When checking the flip-27 source reader PR from @stevenzwu , the current CI did not detect the missing of newly introduced flink dependencies for flink 1.12 and flink1.3. https://github.com/apache/iceberg/pull/2305/files#r740086825
2. In this PR: Flink: Support flink 1.14.0 #3434, it just pass all the check for flink 1.14, but in fact we did nothing when run the test cases.

[stevenzwu]

@openinx this looks good to me.

On a separate note, is iceberg-flink-runtime module still needed after the multi-version support change?

[openinx]

@stevenzwu we don't need the common iceberg-flink-runtime any more, instead we provided a separate flink runtime for different versions, such as iceberg-flink-1.12-runtime, iceberg-flin-1.13-runtime.

[stevenzwu]

@rdblue can you take a look at this PR and merge if it looks good to you?

[rdblue]

Since the tests are running in both 1.12 and 1.13 jobs, we no longer need the flink-common-tests CI job. Can you remove it?

[openinx]

As we are planning to separate the code base for flink 1.12 , flink 1.13, flink 1.14 ( From this comment1, comment2, comment3 ). We don't need this unit tests change now. Let's close it.