Spark: Refactor SparkReadConf use primitive type for confs with default values

[singhpk234]

About Change

Address review feedback #7422 (comment) .

cc @aokolnychyi

[szehon-ho]

Mostly looks good to me. But wanted to double check, is it a backward compatible change?
User will ever get NoSuchMethodError?

[jackye1995]

looks good to me

[jackye1995]

is it a backward compatible change?

Under what case would user have this error? @szehon-ho

[singhpk234]

we can get the values in both long, Long, so using the function call directly would not be problematic but let's say if some one is extending SparkReadConf and over-riding the streamFromTimestamp() might face issue as now the signatures don't match. But it seems like a very niche use case.

Would like to know your thoughts and make the changes accordingly, as streamFromTimestamp() is the only released public method will mark it deprecated, and add a new one with primitive type as well.

[szehon-ho]

Yea I am thinking, if our caller does not recompile their library on newer Iceberg version , they will hit it, but I think its not the normal flow. Thanks for double checking.

[aokolnychyi]

Thanks, @singhpk234!

[amogh-jahagirdar]

Thanks @singhpk234 ! i was thinkiing about @szehon-ho point , I don't think we can set an expectation that people can extend SparkReadConf and have signatures align. So overall, this change looks good to me