Lint package.json files (#3368)

Notable changes in this context:

- simplification of the ESLint calls - there is no longer a combination
of two file/directory lists (one in `package.json` and one in
`.eslintignore`)
- removal of a non-existent path from the `.eslintignore`
- use shorthand declaration for GitHub repository

Normally the new plugin would also sort the scripts in the package.json
alphabetically, but I think the current order is fine, so I deactivated
it.

Is it overkill to introduce a linter plugin just for the `package.json`
files?

In other projects I have seen that such internal changes were marked
with "chore" in the changelog. That's what I've done here. These chore
changes are less interesting for "normal" users.

Please feel free to give me feedback.

package.json

@@ -18,20 +18,17 @@
 		"test:e2e": "NODE_ENV=test jest --selectProjects e2e -i --forceExit",
 		"test:unit": "NODE_ENV=test jest --selectProjects unit",
 		"test:prettier": "prettier . --check",
-		"test:js": "eslint 'js/**/*.js' 'modules/default/**/*.js' 'clientonly/*.js' 'serveronly/*.js' 'translations/*.js' 'vendor/*.js' 'tests/**/*.js' 'config/*'",
+		"test:js": "eslint .",
 		"test:css": "stylelint 'css/main.css' 'fonts/*.css' 'modules/default/**/*.css' 'vendor/*.css' --config .stylelintrc.json",
 		"test:calendar": "node ./modules/default/calendar/debug.js",
 		"config:check": "node js/check_config.js",
 		"lint:prettier": "prettier . --write",
-		"lint:js": "eslint 'js/**/*.js' 'modules/default/**/*.js' 'clientonly/*.js' 'serveronly/*.js' 'translations/*.js' 'vendor/*.js' 'tests/**/*.js' 'config/*' --fix",
+		"lint:js": "eslint . --fix",
 		"lint:css": "stylelint 'css/main.css' 'fonts/*.css' 'modules/default/**/*.css' 'vendor/*.css' --config .stylelintrc.json --fix",
 		"lint:staged": "lint-staged",
 		"prepare": "[ -f node_modules/.bin/husky ] && husky install || echo no husky installed."
 	},
-	"repository": {
-		"type": "git",
-		"url": "git+https://github.com/MagicMirrorOrg/MagicMirror.git"
-	},
+	"repository": "MagicMirrorOrg/MagicMirror",
 	"keywords": [
 		"magic mirror",
 		"magicmirror",
@@ -53,6 +50,7 @@
 		"eslint-plugin-import": "^2.29.1",
 		"eslint-plugin-jest": "^27.6.3",
 		"eslint-plugin-jsdoc": "^48.0.2",
+		"eslint-plugin-package-json": "^0.10.0",
 		"eslint-plugin-unicorn": "^50.0.1",
 		"express-basic-auth": "^1.2.1",
 		"husky": "^8.0.3",