Update for deps

[Nosferican]

Closes #70 #71 #72 #73 #74 #75 #76

Basically, a PR to update a few things which have gathered some dust.

• Updates the StatsBase (StatsAPI) including responsename, updated dof definition, and docs (module is now StatsAPI)
• Updates the compat for deps
• Updates the codemeta to CFF (GitHub lead w/CFF as the preferred standard)
• Updated the CI (actions to newer releases)

I tried updating the show(io, mime, obj) instead of using the 2-args method but didn't work well so that is out of scope for this one.

[codecov[bot]]

Codecov Report

Merging #79 (d880c08) into master (32659ae) will increase coverage by 0.08%. The diff coverage is 91.66%.

@@            Coverage Diff             @@
##           master      #79      +/-   ##
==========================================
+ Coverage   90.22%   90.31%   +0.08%     
==========================================
  Files           9        9              
  Lines         696      702       +6     
==========================================
+ Hits          628      634       +6     
  Misses         68       68              

Impacted Files	Coverage Δ
src/Econometrics.jl	0.00% <ø> (ø)
src/solvers.jl	89.02% <66.66%> (ø)
src/main.jl	91.83% <100.00%> (+0.08%)	:arrow_up:
src/statsbase.jl	87.50% <100.00%> (+0.16%)	:arrow_up:
src/mlj-model-interface.jl	100.00% <0.00%> (ø)
src/structs.jl	89.09% <0.00%> (+0.41%)	:arrow_up:

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