Deprecate CodeCov for Codecov

[christopher-dG]

I never realized that it was spelled wrong the whole time...
I'm not sure if this is actually worth it tbh but I do like keeping things accurate.

[codecov]

Codecov Report

Merging #34 into master will decrease coverage by 0.06%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master     #34      +/-   ##
=========================================
- Coverage   79.46%   79.4%   -0.07%     
=========================================
  Files          11      11              
  Lines         336     369      +33     
=========================================
+ Hits          267     293      +26     
- Misses         69      76       +7

Impacted Files	Coverage Δ
src/generate.jl	74.48% <ø> (ø)	⬆️
src/plugins/codecov.jl	83.33% <100%> (ø)	⬆️
src/plugins/documenter.jl	80.3% <0%> (-1.52%)	⬇️

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