bugfix: unit test broken everywhere by package change(#46344)

Openmpi provider statements were changed in #46102. The package change
was fine in and of itself, but apparently one of our tests depends on
the precise constraints used in those statements. I updated the test
to remove the checks for constraints that were removed.

lib/spack/spack/test/cmd/providers.py

@@ -31,7 +31,6 @@ def test_it_just_runs(pkg):
                 "mpilander",
                 "mvapich2",
                 "openmpi",
-                "openmpi@1.6.5",
                 "openmpi@1.7.5:",
                 "openmpi@2.0.0:",
                 "spectrum-mpi",