testsuite: Remove test that should not have been backported [PR105608]

testsuite: Remove test that should not have been backported [PR105608]

This test (backported as part of r13-8257, from r14-8465) was not meant to
be backported, since it fails on some platforms without other GCC 14 patches
that will not be backported. Remove it from the 13 branch.

gcc/testsuite/ChangeLog:

	PR preprocessor/105608
	* g++.dg/pch/line-map-3.C: Removed.
	* g++.dg/pch/line-map-3.Hs: Removed.