refactor: use workspaces to enable testing of bumped versions

[morremeyer]

This PR makes use of yarn workspaces to enable local testing even when versions are bumped.

It also:

• bumps various dependencies to up-to-date versions so that the build and type checking are successful.
• removes node 16 from the testing workflows since current versions of Gatsby require at least node 18
• adds tests for both the bank2ynab-converter and the web-app
• adds a results-${package} job to every test workflow that checks the result of the matrix job. With that, the required checks can be updated to only require the following jobs: results-bank2ynab-converter, results-parsers, results-web-app instead of updating the required checks every time a new node version is added to the matrix job.

There's two things that need careful review:

• I had to append /src to the imports of ynap-parsers and ynap-bank2ynab-converter. I have no idea if this is how it should be or if it will break when the packages are released .
• I had to add an import for Buffer in the web app to fix a Buffer is undefined error. I tested the web-app by running yarn build and yarn start and then converting a file.

@leolabs This change will enable #619 to run successful tests and be merged.

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.01 🎉

Comparison is base (89a4907) 91.09% compared to head (34195eb) 91.10%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #646      +/-   ##
==========================================
+ Coverage   91.09%   91.10%   +0.01%     
==========================================
  Files          25       25              
  Lines         865      866       +1     
  Branches      234      234              
==========================================
+ Hits          788      789       +1     
  Misses         70       70              
  Partials        7        7              

Impacted Files	Coverage Δ
packages/ynap-parsers/src/bank2ynab/bank2ynab.ts	68.96% <ø> (ø)
...ackages/ynap-parsers/src/util/read-encoded-file.ts	94.44% <100.00%> (+0.32%)	⬆️

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[morremeyer]

@leolabs This is now ready for review, all notes above. If you're happy with it, can you also update the required checks for the PRs as described?

Thanks!

[morremeyer]

Merged this in the fork with envelope-zero#1