Replace unit tests marked by the @pytest.mark.local decorator.

[prjemian]

Replace the three tests. For now, restore the @pytest.mark.local decorator. As noted in #809, the current tests do not reveal if there is a problem with the apstools.devices.positioner_soft_done or the tests themselves. Refactor with simpler tests that are focused on features of the support, as noted in #810.

Originally posted by @prjemian in #748 (comment)

[prjemian]

Focus on creating tests for lines of code not already covered by tests. Coverage of positioner_soft_done.py shows these lines needs test coverage:

apstools/apstools/devices/positioner_soft_done.py

Lines 246 to 249 in 7d6ac98

	if not self.inposition:
	self.setpoint.put(self.position)
	timed_pause()
	self.cb_readback() # re-evaluate soft done Signal

[prjemian]

No test failures in the recent CI. Even with the local marks commented out. That's encouraging!

Still, this line fails sometimes (local or CI):

apstools/apstools/devices/tests/test_positioner_soft_done.py

Line 233 in ef5371a

assert pos.setpoint.get(use_monitor=False) == rb_mid # FIXME: fails sometimes 1.0 == 0.5

[prjemian]

While these tests are now succeeding, the fix is part of #954.