builtins: implement ST_IsEmpty and ST_IsCollection

[erikgrinaker]

ST_IsCollection does not handle geopb.ShapeType_Geometry in any special way, and will always return false - is this sufficient?

Release note (sql change): Implement the geometry builtins ST_IsEmpty
and ST_IsCollection.

Closes #48954.
Closes #48955.

[blathers-crl]

Thank you for contributing to CockroachDB. Please ensure you have followed the guidelines for creating a PR.

My owl senses detect your PR is good for review. Please keep an eye out for any test failures in CI.

I have added a few people who may be able to assist in reviewing:

• @otan (author of geo/geomfn: implement ST_IsCollection({geometry}) #48954, author of geo/geomfn: implement ST_IsEmpty({geometry}) #48955)

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is otan.}

[cockroach-teamcity]

This change is 

[otan]

ST_IsCollection does not handle geopb.ShapeType_Geometry in any special way, and will always return false - is this sufficient?

ShapeType_Geometry is never returned so we should be ok!

[erikgrinaker]

I'm guessing the test failure is an unrelated non-deterministic failure, would you mind rerunning it @otan?

[otan]

yeah that's not you. i could re-run it, but bors will do it for me.

thank you again!

[otan]

bors r+

[craig]

Build succeeded:

• GitHub CI (Cockroach)