build: cache yarn directory instead of node_modules

[malept]

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.

Summarize your changes:

See: https://github.com/actions/cache/blob/v1.1.0/examples.md#node---yarn

[codecov]

Codecov Report

Merging #1404 into master will decrease coverage by 0.09%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #1404     +/-   ##
=========================================
- Coverage   70.05%   69.96%   -0.1%     
=========================================
  Files          73       73             
  Lines        2104     2104             
  Branches      389      389             
=========================================
- Hits         1474     1472      -2     
- Misses        480      491     +11     
+ Partials      150      141      -9

Impacted Files	Coverage Δ
packages/api/core/src/util/electron-version.ts	84.31% <0%> (-3.93%)	⬇️
packages/api/core/src/api/import.ts	58.82% <0%> (ø)	⬆️

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