Fix class descriptions of ghosting functors

[moosebuild]

Job Coverage, step Generate coverage on 0284d35 wanted to post the following:

Coverage

	548364	#3972 0284d3
	Total	Total	+/-	New
Rate	62.17%	62.17%	-0.00%	-
Hits	72419	72417	-2	0
Misses	44058	44060	+2	0

Diff coverage report

Full coverage report

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