Preventing NONE Primary Role Hiring

[Windchild292]

The NONE Role is supposed to be a secondary role only. This prevents you from hiring a person with NONE as a primary role.

The second commit refactors the personnel role methods into streams

[codecov]

Codecov Report

Merging #2667 (b329457) into master (c4db818) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##             master    #2667      +/-   ##
============================================
- Coverage     10.72%   10.72%   -0.01%     
+ Complexity     3826     3821       -5     
============================================
  Files           704      704              
  Lines         98446    98428      -18     
  Branches      16355    16345      -10     
============================================
- Hits          10561    10553       -8     
+ Misses        86508    86493      -15     
- Partials       1377     1382       +5     

Impacted Files	Coverage Δ
.../mekhq/campaign/personnel/enums/PersonnelRole.java	35.33% <0.00%> (+4.41%)	⬆️
MekHQ/src/mekhq/gui/CampaignGUI.java	0.00% <0.00%> (ø)
.../src/mekhq/gui/dialog/HireBulkPersonnelDialog.java	0.00% <0.00%> (ø)
MekHQ/src/mekhq/campaign/universe/Systems.java	41.43% <0.00%> (-0.80%)	⬇️
...Q/src/mekhq/campaign/universe/RegionPerimeter.java	83.33% <0.00%> (-0.70%)	⬇️
...ekhq/campaign/universe/RandomFactionGenerator.java	58.40% <0.00%> (-0.40%)	⬇️
...ekHQ/src/mekhq/campaign/market/ContractMarket.java	58.62% <0.00%> (-0.40%)	⬇️
MekHQ/src/mekhq/campaign/universe/Planet.java	26.07% <0.00%> (-0.23%)	⬇️
MekHQ/src/mekhq/campaign/mission/AtBContract.java	19.07% <0.00%> (-0.12%)	⬇️

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