Fix proportion female

[kellijohnson-NOAA]

What is the feature?

• Reverts proportion_female to a single constant of 0.5

How have you implemented the solution?

• Using a constant scalar.

Does the PR impact any other area of the project, maybe another repo?

• The case studies need to be changed to not set proportion_female.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 8.57143% with 64 lines in your changes missing coverage. Please review.

Project coverage is 66.06%. Comparing base (39d0743) to head (577a68b).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
inst/include/population_dynamics/fleet/fleet.hpp	0.00%	31 Missing ⚠️
...nst/include/distributions/functors/normal_lpdf.hpp	0.00%	18 Missing ⚠️
...nclude/distributions/functors/multinomial_lpmf.hpp	0.00%	13 Missing ⚠️
...distributions/functors/density_components_base.hpp	0.00%	2 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (39d0743) and HEAD (577a68b). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (39d0743)	HEAD (577a68b)
	2	1

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #654       +/-   ##
===========================================
- Coverage   78.88%   66.06%   -12.82%     
===========================================
  Files          36       19       -17     
  Lines        1975      725     -1250     
  Branches      141      196       +55     
===========================================
- Hits         1558      479     -1079     
+ Misses        374      165      -209     
- Partials       43       81       +38     

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[kellijohnson-NOAA]

Now in cleanup_dev branch to be brought into dev.