Remove unnecessary spec for dummy block

[albeanth]

armi/armi/reactor/converters/axialExpansionChanger.py

Lines 752 to 753 in 753660d

	elif b.hasFlags(Flags.DUMMY):
	self.determineTargetComponent(b, Flags.COOLANT)

The axial expansion target component for the dummy block is never used. We don't need to enforce that a coolant component be the axial expansion target component for the dummy block. _setTargetComponent can also just loop over the non-dummy blocks.

[john-science]

I really hope the dummy block is never used.

But, great! Can't wait!

[jakehader]

@albeanth - what's the progress on this and other axial expansion improvements?

[albeanth]

@albeanth - what's the progress on this and other axial expansion improvements?

• this specifically? Nothing. But it should be as simple as deleting those two lines and maybe updating/adding a test.
• there will be a large refactor of axialExpansionChanger.py soon. Refactor Axial Expansion #1435 has been blocked by downstream updates but is now unblocked and is in line to go through.
• Add New Component Axial Linking Approach #1376 is planned to go through sometime between now and October.
• I have a new feature branch for axial expansion documentation... Someday that will go through... The scope of it is quite large
  so that is going to take time (time I don't really have right now, tbh ☹️ ). main...albeanth:armi:axial_exp_documentation_finally

[drewj-tp]

Grabbing this because I'm already mucking around with some axial expansion related things and this seems like good thing to grab as well