[r] Fix query conditions on enumerated columns

[johnkerl]

Works in Python: https://gist.github.com/johnkerl/3d1279b0e3bd9e599d541774419faa54
Not in R: https://gist.github.com/johnkerl/d22373ff55cca23cd23672dae547b3de

Note s3://tiledb-johnkerl/s/v/pbmc3k in the above gists is nothing other than tiledbsoma.io.from_h5ad of
https://github.com/single-cell-data/TileDB-SOMA/blob/main/apis/python/testdata/pbmc3k.h5ad

Needs:

• Bugfix
• Unit-test coverage

See also #1862

[johnkerl]

[sc-36509]

[eddelbuettel]

Fixed by TileDB-Inc/TileDB-R#614 as the actual parsing is done in the tiledb package.

[johnkerl]

@eddelbuettel thanks! Looking forward to closing this issue once this functionality is available in TileDB-SOMA. (Remaining PRs including apis/R/DESCRIPTION in this repo, and unit-test coverage in this repo, after you've got TileDB-R tagged & in Conda.)