[SPARK-49942][SQL] Rename `errorClass` to `condition` in `classifyException()`

[MaxGekk]

What changes were proposed in this pull request?

In the PR, I propose to rename the errorClass parameter to condition in JdbcDialect.classifyException and in JdbcUtils.classifyException.

Why are the changes needed?

To follow new naming convention introduced by https://github.com/apache/spark/pull/44902.

Does this PR introduce any user-facing change?

No. The classifyException method has not been released yet.

How was this patch tested?

By running the existing GitHub actions.

Was this patch authored or co-authored using generative AI tooling?

No.