Remove rpy2 workaround in conftest.py

[orlitzky]

We currently have a hack in conftest.py for (the possibly absent) rpy2 in src/sage/interfaces/r.py, but apparently everything is fine without it.

[github-actions]

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[tobiasdiez]

I'm a bit confused about how this is working for you as pytest is not able to understand the #needs annotations, neither global, block nor line comments. I also would be hesitant to add that feature to pytest.

The "this is a hack" comment mostly referred to that the file using rpy2 should throw a FeatureNotFound error if rpy2 is not available (instead of a ModuleNotFoundError), in which case the file then automatically gets ignored by

sage/conftest.py

Lines 149 to 152 in e37154c

	except FeatureNotPresentError as exception:
	pytest.skip(
	f"unable to import module {self.path} due to missing feature {exception.feature.name}"
	)

[orlitzky]

Well TBH I assumed that it was not working, and that since it works now, I fixed it. But it was working to begin with!

[orlitzky]

Without changing anything in r.py:

=================================================================== short test summary info ===================================================================
SKIPPED [1] conftest.py:149: unable to import module /home/mjo/src/sage.git/src/sage/interfaces/r.py due to missing feature rpy2
===================================================================== 1 skipped in 0.54s =====================================================

[tobiasdiez]

That's of course very nice ;-)