## What changes were proposed in this pull request?
Currently, File source v2 allows each data source to specify the supported data types by implementing the method `supportsDataType` in `FileScan` and `FileWriteBuilder`.
However, in the read path, the validation checks all the data types in `readSchema`, which might contain partition columns. This is actually a regression. E.g. Text data source only supports String data type, while the partition columns can still contain Integer type since partition columns are processed by Spark.
This PR is to:
1. Refactor schema validation and check data schema only.
2. Filter the partition columns in data schema if user specified schema provided.
## How was this patch tested?
Unit test
Closes#24203 from gengliangwang/schemaValidation.
Authored-by: Gengliang Wang <gengliang.wang@databricks.com>
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>
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