Deprecate File Source V1

[fuyufjh]

The new batch-reading feature was done for v2. #15358

Time to deprecate the old file source.

We can keep the old code for existing users, but the default behavior should be using v2 i.e. No _v2 prefix in s3_v2

[neverchanje]

#16234

I once created a similar issue.

[fuyufjh]

#16234 was closed by #16337.

We can keep the old code for existing users, but the default behavior should be using v2 i.e. No _v2 prefix in s3_v2

So, can we do this?