build(api): do not bundle dev dependencies in prod

Previously, Fishery and nock were bundled into the production bundle
even though the functions in files that imported them were NOT
referenced in the production code. We can set `sideEffects: false` in
`package.json` to treat all files as having no side-effects.

I don't _think_ that we have any files that would have side-effects, but
let's see how it goes.

Related to #83

apps/api/package.json

@@ -2,6 +2,7 @@
   "name": "@serieslist/api",
   "version": "1.0.0",
   "type": "module",
+  "sideEffects": false,
   "scripts": {
     "build": "rimraf dist && NODE_ENV=production tsx bin/build.ts",
     "build:docker": "(cd ../.. && docker buildx build --push --cache-to type=gha,mode=max,scope=webapp --cache-from type=gha,scope=webapp -t ghcr.io/joosepalviste/serieslist-api:latest -f apps/api/Dockerfile --target production .)",