Don't show conflicts between .mohidden files

[ignamiranda]

Is your feature request related to a problem? Please describe.
If you hide the same files in two mods, MO2 will show the mohidden files as conflicting. This makes it harder to parse through other conflicts that are actually meaningful.

Describe the solution you'd like
Files with the .mohidden extension should not be shown at all in the conflicts tab of a mod and shouldn't cause mods to be highlighted as conflicts in the mod list.

[qudix]

PR already exists for this: #2148
Not sure why it hasn't been accepted yet, but I'll poke a bit.