[meta] use npmignore to autogenerate an npmignore file

.gitignore

@@ -61,3 +61,5 @@ typings/
 npm-shrinkwrap.json
 package-lock.json
 yarn.lock
+
+.npmignore

package.json

@@ -5,16 +5,17 @@
 	"main": "index.js",
 	"sideEffects": false,
 	"scripts": {
-		"version": "auto-changelog && git add CHANGELOG.md",
-		"postversion": "auto-changelog && git add CHANGELOG.md && git commit --no-edit --amend && git tag -f \"v$(node -e \"console.log(require('./package.json').version)\")\"",
+		"prepack": "npmignore --auto --commentLines=autogenerated",
 		"prepublish": "not-in-publish || npm run prepublishOnly",
 		"prepublishOnly": "safe-publish-latest",
 		"lint": "eslint --ext=js,mjs .",
 		"postlint": "es-shim-api --bound --skip-shim-returns-polyfill",
 		"tests-only": "nyc tape 'test/**/*.js'",
 		"pretest": "npm run lint",
 		"test": "npm run tests-only",
-		"posttest": "aud --production"
+		"posttest": "aud --production",
+		"version": "auto-changelog && git add CHANGELOG.md",
+		"postversion": "auto-changelog && git add CHANGELOG.md && git commit --no-edit --amend && git tag -f \"v$(node -e \"console.log(require('./package.json').version)\")\""
 	},
 	"repository": {
 		"type": "git",
@@ -52,6 +53,7 @@
 		"eslint": "=8.8.0",
 		"has-strict-mode": "^1.0.1",
 		"in-publish": "^2.0.1",
+		"npmignore": "^0.3.0",
 		"nyc": "^10.3.2",
 		"reflect.ownkeys": "^1.1.1",
 		"safe-publish-latest": "^2.0.0",
@@ -67,5 +69,10 @@
 		"commitLimit": false,
 		"backfillLimit": false,
 		"hideCredit": true
+	},
+	"publishConfig": {
+		"ignore": [
+			".github/workflows"
+		]
 	}
 }