chore: require Node 12 for all packages

[malept]

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• The changes are appropriately documented (if applicable).
• The changes have sufficient test coverage (if applicable).
• The testsuite passes successfully on my local machine (if applicable).

Summarize your changes:

Also upgrades all of the dependencies as necessary.

[codecov]

Codecov Report

Merging #2281 (0984c1c) into master (564a445) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2281      +/-   ##
==========================================
+ Coverage   73.14%   73.17%   +0.03%     
==========================================
  Files          74       74              
  Lines        2193     2196       +3     
  Branches      413      413              
==========================================
+ Hits         1604     1607       +3     
  Misses        418      418              
  Partials      171      171              

Impacted Files	Coverage Δ
...s/plugin/local-electron/src/LocalElectronPlugin.ts	100.00% <0.00%> (ø)

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