pgwire: transmit 24:00 correctly for Time/TimeTZ

[otan]

Would resolve #44548, but has a few blockers to sort out.

We previously relied on golang's time.Time library to return 24:00 time
for us; however, time.Time does not parse 24:00 well, nor does it print
24:00 as on the same day (it uses the next day).

As such, when parsing or emitting time.Time, we have to be super weary
of how we output 24:00 time. Two major changes:

• update lib/pq to pick up encode: fix 2400 time encoding for time/timetz lib/pq#944 such that
  it can parse 24:00 time externally.
• update places where time.Time is parsed from a go driver or lib/pq to
  correctly handle 24:00 cases.

Release note (sql change, bug fix): 24:00 time now displays correctly in
the cli, returning 0001-01-02 00:00:00. Furthermore, backups correctly
emit and read in 24:00 time properly.

[cockroach-teamcity]

This change is 

[knz]

What about taking this opportunity to get rid of lib/pq and go's sql driver.Value abstraction and instead use pgx and our own parsing into datums. There is a bunch of issues in the CLI project that would go away with this move, and it would unblock your PR.

[otan]

Another way to go about it :) I mainly wanted to write and make sure this worked [hence the draft, but you know also a quick fix if we were bothered] because I was thinking about writing a blog post of the intricacies of dealing with time related data types, and this is an example of golang's time module being stubborn all the way down.