Added support for ns #1169

[zaryab-ali]

@kevinjqliu made the changes suggested in the previous comments and added the test case for the functionality

[kevinjqliu]

Thanks for the contribution!

Can you add a few more test scenarios?

• Time64Type with us precision
• Time64Type with ns precision, _downcast_ns_timestamp_to_us not set
• Time64Type with ns precision, _downcast_ns_timestamp_to_us is set

I also want to make sure that downcast works for "Time64Type with ns precision". So let's add a test on the read/write path to verify this.

[zaryab-ali]

@kevinjqliu i have a few questions about the these test case scenarios

• the first scenario is already present i think, test_pyarrow_time64_us_to_iceberg function checks with us precision
• secondly, can you please explain a bit about the test case you want me to write on the read/write path, what file should that be in and what specifically should it test for

[JE-Chen]

You can find some information in my previous PR.
#1206

[kevinjqliu]

• Time64Type with us precision. This was already supported by the previous code.
• Time64Type with ns precision, _downcast_ns_timestamp_to_us not set. Should error
• Time64Type with ns precision, _downcast_ns_timestamp_to_us is set. Should downcast precision to us
• Able to write pyarrow dataframe with a column with Time64Type with ns precision.

You can use #848 as an example where timestamp downcast was implemented