Corner Case Determining Latest Benchmarks

[stanbrub]

For release queries, there is a function latest_comparable_benchmarks that returns only the latest benchmarks that have greater than two versions. This is to avoid having obsolete benchmarks or brand new benchmarks that have nothing to compare.

This is achieved, because of a lack of build number in the product, by taking the timestamps of the benchmarks and converting them to an epoch day. The idea is to grab only benchmarks for the most recent day.

The problem is that sometimes adhoc benchmarks will be within a day local time but span days UTC. So some benchmarks get weeded out that shouldn't. (It doesn't look like this problem affect nightly runs, because they are run in the wee hours of the morning U.S.)

• Broaden the epoch day to cover some of the next day
• Parquet between 0.29.0 and 0.30.0 has obsolete and new benchmarks.