Fix 'yarn pack' (#238)

The `yarn pack` command is run by the `npm-publish` action prior to
publishing the package. Unfortunately, this command does not work as the
`prepack` lifecycle script is overridden to run `yarn build:clean`,
which was removed when this repo was converted to use `tsup` for
building. `tsup` already has a way of clearing `dist` via a `--clean` flag, so
this commit modifies the `build` script to use it and modifies the prepack
script to run `yarn build` instead of `yarn build:clean`.

package.json

@@ -26,7 +26,7 @@
     "dist"
   ],
   "scripts": {
-    "build": "tsup && yarn build:types",
+    "build": "tsup --clean && yarn build:types",
     "build:docs": "typedoc",
     "build:types": "tsc --project tsconfig.build.json",
     "lint": "yarn lint:eslint && yarn lint:constraints && yarn lint:misc --check && yarn lint:dependencies --check && yarn lint:changelog",

scripts/prepack.sh

@@ -8,4 +8,4 @@ if [[ -n $SKIP_PREPACK ]]; then
   exit 0
 fi
 
-yarn build:clean
+yarn build