Add an assert to prevent returning true when asking if invalid_uint is the id of a vertex of a 1st order element

[GiudGiud]

refs #4122

we could also do

  libmesh_assert_less (n, n_nodes());

instead. Seems like it would be just as invalid to me

[GiudGiud]

failures are fixed by idaholab/moose#30196

[moosebuild]

Job Coverage, step Generate coverage on d878831 wanted to post the following:

Coverage

	e947c6	#4123 d87883
	Total	Total	+/-	New
Rate	63.32%	63.32%	+0.00%	100.00%
Hits	74334	74341	+7	16
Misses	43055	43056	+1	0

Diff coverage report

Full coverage report

This comment will be updated on new commits.

[roystgnr]

This works for me as-is, but could we use libmesh_dbg_var(n) in the argument lists rather than libmesh_ignore(n) in the bodies?

[GiudGiud]

ok let me change that

[roystgnr]

Let's wait until idaholab/moose#30196 is fully merged so we don't add yet another spurious recipe failure to libMesh PRs, but otherwise this is good to go.

[GiudGiud]

MOOSE patch is merged, test failure unrelated

[GiudGiud]

nevermind

[moosebuild]

Job Test MOOSE debug on d878831 : invalidated by @GiudGiud

should be fixed now

[moosebuild]

Job Test MOOSE ARM mac on d878831 : invalidated by @GiudGiud

unrelated