Adjust the support of Spark 2.x version

[baiyangtx]

Backgroud

The community is pushing forward the upgrading the iceberg version to 1.1.0, #989
And in iceberg 1.1.0, iceberg changes the spark2 module to spark 2.4, but Spark2.x version supported by Arctic is 2.3, and Arctic dose some extra things to support Spark SQL in spark 2.x verison.

I have bean researched that the spark 2.x version and features supported by datalake formats.

Format	Spark2.x Version	DataFrameAPI	Spark SQL
Iceberg	2.4	√	X
Hudi	2.4.3+	√	√
Paimon	2.4	√	X
Delta	NotSupported in lasted version

There several options:

1. Remove support of Spark 2.x, Arctic will only support Spark 3.1+
2. Change the Spark 2.3 support to 2.4, and support Dataframe API only.
3. Change the Spark 2.3 support to 2.4, and support Dataframe API and Spark SQL.

[dupen01]

It doesn't matter to me because I use spark3😁

[GavinH1984]

Vote for option 1~~~😁

[pan3793]

Vote for option 1. Spark 2 was EOL for quite a long time

[Aireed]

Vote for option 1

[zhongqishang]

Vote for option 1

[zhoujinsong]

We have stopped supporting spark 2.x for Mixed formats.