feat(test): moving unit tests over to vitest

[erunion]

🧰 Changes

I've been wildy impressed with Vitest so this is moving us off Jest and over to that. The performance gains aren't going to break the bank, but I'll happily take a couple seconds off of the api suite any day.

◀️ Before

api

Test Suites: 18 passed, 18 total
Tests:       7 todo, 216 passed, 223 total
Snapshots:   0 total
Time:        29.639 s
Ran all test suites matching /test\/core\/index.test.ts|test\/core\/getJSONSchemaDefaults.test.ts|test\/core\/parseResponse.test.ts|test\/core\/prepareParams.test.ts|test\/core\/prepareAuth.test.ts|test\/auth.test.ts|test\/index.test.ts|test\/cache.test.ts|test\/cli\/codegen\/languages\/typescript\/utils.test.ts|test\/cli\/codegen\/languages\/typescript.test.ts|test\/cli\/storage.test.ts|test\/fetcher.test.ts|test\/cache-tmp.test.ts|test\/dist.test.ts|test\/cache-custom.test.ts|test\/config.test.ts|test\/integration.test.ts|test\/server.test.ts/i.
npx jest --coverage   77.67s user 5.05s system 275% cpu 30.033 total

httpsnippet-client-api

Test Suites: 1 passed, 1 total
Tests:       68 passed, 68 total
Snapshots:   0 total
Time:        4.174 s, estimated 5 s
Ran all test suites.
npx jest  6.69s user 0.40s system 149% cpu 4.739 total

⏭️ After

api

 Test Files  18 passed (18)
      Tests  216 passed | 7 todo (223)
   Start at  18:22:46
   Duration  26.88s (transform 817ms, setup 305ms, collect 4.15s, tests 35.72s, environment 2ms, prepare 1.38s)

npx vitest run  56.27s user 4.04s system 220% cpu 27.316 total

httpsnippet-client-api

 Test Files  1 passed (1)
      Tests  68 passed (68)
   Start at  18:24:35
   Duration  3.32s (transform 184ms, setup 0ms, collect 245ms, tests 2.87s, environment 0ms, prepare 52ms)

npx vitest run  5.34s user 0.50s system 155% cpu 3.750 total

[kanadgupta]

looks good for the most part, just a few small comments! very jealous of how easy of a drop-in replacement this was... readmeio/rdme#857 is looking rough 😬

[kanadgupta]

love how we don't need any additional packages to support TS 😌

[kanadgupta]

we really were living like gremlins huh