test_ogrsf: do not build test program if BUILD_TESTING=OFF

[echoix]

What does this PR do?

Skip building test_ogrsf program if BUILD_TESTING is OFF.
I noticed in GRASS' Docker builds where gdal is built from source, that some test targets are still being built. This non-default app is being built by default (notice the contradiction here). Either the test_ogrsf should be non-default, or built only when building testing tools. It seems that in OGR 3.5.0-era, test_ogrsf was built by default but not installed (in autotools builds), see

gdal/NEWS.md

Line 8237 in 9bed24f

* generate test_ogrsf by default (but not installed)

I chose to not build that app if BUILD_TESTING is not ON, similar to how some sample programs were not built in the issues/PRs listed below.

With feedback, I could also add more apps to not build when tests are not built, but they don't seem to be built unconditionally.

There is also my_test_sqlite3_ext.c that seems to be always built. Maybe a solution like the issues/PRs below should apply, but I was unsure of the implications, so I left it as is for now.

	[1030/1446] Building C object ogr/ogrsf_frmts/sqlite/CMakeFiles/my_test_sqlite3_ext.dir/my_test_sqlite3_ext.c.o
	[1031/1446] Linking C shared module gdalplugins/my_test_sqlite3_ext.so

What are related issues/pull requests?

Similar to my older issue #9856, that lead to #9857 and #9864

Tasklist

• AI (Copilot or something similar) supported my development of this PR
• Make sure code is correctly formatted (cf pre-commit configuration)
• Add test case(s)
• Add documentation
• Updated Python API documentation (swig/include/python/docs/)
• Review
• Adjust for comments
• All CI builds and checks have passed
• ADD YOUR TASKS HERE

Environment

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