[1.6.x] Skipped some broken tests on Oracle GIS; refs #23504.

Backport of 7fce7f51ef from master
[1.6.x] Removed unnecessary order_by() from a GIS test that crashed Oracle.

Oracle cannot order_by() a TextField; refs #23504.

Backport of 7fc13178d6 from master
[1.6.x] Skipped a broken GIS test on Oracle; refs #23504.

Backport of 828edc5ba9 from master
[1.6.x] Made a GIS test work on Oracle.

Thanks Josh Smeaton and Claude Paroz for advice.

Backport of 7add30df01 from master