Fixed unitTypeCode not being used in accessLevelUnit

[kolaente]

While doing some refactoring for #6418 I discovered this function was essentially useless.

[lunny]

@kolaente also find HasAccessUnit is not used any more. Maybe we could remove it.

[lunny]

Since canBeAssigned referenced hasAccessUnit and it in fact gave unitType as UnitTypeCode. This haven't really taken an effect.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@b48be19). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #6419   +/-   ##
=========================================
  Coverage          ?   38.87%           
=========================================
  Files             ?      365           
  Lines             ?    51393           
  Branches          ?        0           
=========================================
  Hits              ?    19979           
  Misses            ?    28547           
  Partials          ?     2867

Impacted Files	Coverage Δ
models/repo_permission.go	72.02% <100%> (ø)

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[kolaente]

Since canBeAssigned referenced hasAccessUnit and it in fact gave unitType as UnitTypeCode. This haven't really taken an effect.

Sure, but I'd do that in #6418 as there are a lot other unused functions as well which I removed in that pr also.

[kolaente]

Should I send a backport?

[lafriks]

I think yes