geo: various geospatial built-in fixes

[rharding6373]

geo: support null input for geohash builtins

Allows and adds support for NULL inputs for the st_pointfromgeohash and
st_geomfromgeohash built-ins.

Epic: None
Informs: #111157

Release note (bug fix): Fixes null input handling for the geospatial
built-ins st_pointfromgeohash and st_geomfromgeohash.


geo: allow st_makeenvelope min/max bounds to be reversed

Postgis allows xmin/ymin to be greater than xmax/ymax respectively in
st_makeenvelope, but the geom library does not allow this when
converting Bounds to Polygon. Instead, we build the polygon explicitly
from the provided min/max coordinates.

Epic: None
Fixes: #111157

Release note (bug fix): The geospatial st_makeenvelope built-in now
correctly supports xmin or ymin to be greater than xmax or ymax,
respectively.

[cockroach-teamcity]

This change is 

[DrewKimball]

Nice work!

Reviewed 2 of 2 files at r1, 2 of 2 files at r2, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @rharding6373)

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pkg/sql/sem/builtins/geo_builtins.go line 1133 at r1 (raw file):

			ReturnType: tree.FixedReturnType(types.Geometry),
			Fn: func(_ context.Context, evalCtx *eval.Context, args tree.Datums) (tree.Datum, error) {
				if tree.DNull.Compare(evalCtx, args[0]) == 0{

[nit] Elsewhere we just directly compare args with tree.DNull using ==. Did you find a case where that doesn't work?

[rharding6373]

TFTR!

Reviewable status: complete! 0 of 0 LGTMs obtained (and 1 stale) (waiting on @DrewKimball)

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pkg/sql/sem/builtins/geo_builtins.go line 1133 at r1 (raw file):

Previously, DrewKimball (Drew Kimball) wrote…

[nit] Elsewhere we just directly compare args with tree.DNull using ==. Did you find a case where that doesn't work?

That's just how I happened to write it out. Thanks for the suggestion!

[rharding6373]

I created a new issue for the test failure, which is an unrelated randomized CDC test: #113842

[rharding6373]

TFTR!

bors r+

[craig]

Build succeeded:

• Bazel Essential CI (Cockroach)