fix: lower target to support Webpack 4

[JessicaSachs]

This PR would fix #1073 and target es2019 instead of dropping support for Webpack 4 (which I don't think we should do -- a lot of users are still stuck on Webpack 4, despite how long it has been out).

We're mainly having issues because we use nullish coalescing internally. This requires a target of es2019 instead of es2020. https://esbuild.github.io/content-types/#javascript

Also would fix cypress-io/cypress#21874

[codecov]

Codecov Report

Merging #1085 (6ffbedd) into main (6d3f42e) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1085      +/-   ##
==========================================
- Coverage   99.64%   99.64%   -0.01%     
==========================================
  Files        2135     2135              
  Lines      229241   229241              
  Branches      980      978       -2     
==========================================
- Hits       228432   228427       -5     
- Misses        788      793       +5     
  Partials       21       21              

Impacted Files	Coverage Δ
src/modules/finance/index.ts	99.31% <0.00%> (-0.69%)	⬇️
src/modules/internet/user-agent.ts	86.37% <0.00%> (-0.58%)	⬇️

[Shinigami92]

We should add a CI run for node14.6 or at least the lowest target we support
See also #1052 for my own tries

[Shinigami92]

For tomorrows meeting: I personally find it totally weird that we need to support >2 years old out of date packages, and even if this lowers our target I lost trust in esbuild a bit, because of evanw/esbuild#2315
They are saying that it was because we used esno/tsx, but even now we build it to use native js and it produced the same result in my other branch 🤷
I also don't like that we cannot see which tools and packages out there in the world are possibly not compatible to es20XX and which not. We have a potential table about node versions, but from where can we find out which tools support version xy?
That said, we said that we do not want to support node v12 because it got EOL and so node v14 is the latest "legacy" LTS and it fully supports es2020 🤷
I mean, it is just weird that folks depend on webpack v4 that is out of date, don't get updates (as far as I know) and is not compatible to modern syntax anymore
Is webpack v4 now the new IE11 or what?!

... oops, this turned into a little rant ... 😅

[JessicaSachs]

Shini and I spoke. We'll be supporting es2019 + Webpack 4.

[xDivisionByZerox]

I totally do not understand how this works but if you ensure that it does I'm fine with this.