[meta] switch from files to npmignore

.gitignore

@@ -6,3 +6,5 @@ node_modules
 npm-shrinkwrap.json
 package-lock.json
 yarn.lock
+
+.npmignore

package.json

@@ -3,14 +3,8 @@
 	"version": "5.1.6",
 	"description": "utility library for parsing asn1 files for use with browserify-sign.",
 	"main": "index.js",
-	"files": [
-		"asn1.js",
-		"aesid.json",
-		"certificate.js",
-		"fixProc.js",
-		"index.js"
-	],
 	"scripts": {
+		"prepack": "npmignore --auto --commentLines=autogenerated",
 		"lint": "eslint --ext=js,mjs .",
 		"tests-only": "tape 'test/**/*.js'",
 		"pretest": "npm run lint",
@@ -38,6 +32,7 @@
 		"aud": "^2.0.4",
 		"auto-changelog": "^2.4.0",
 		"eslint": "=8.8.0",
+		"npmignore": "^0.3.1",
 		"tape": "^5.7.5"
 	},
 	"engines": {
@@ -50,5 +45,11 @@
 		"commitLimit": false,
 		"backfillLimit": false,
 		"hideCredit": true
+	},
+	"publishConfig": {
+		"ignore": [
+			".github/workflows",
+			"test"
+		]
 	}
 }