This is what makes Eslint so great. If you extend Airbnb's (or write your own very strict) config, it will really enforce best practices for things like this.
I think running eslint --fix will even change your "let"s to "const"s where appropriate, but don't quote me on that.
I think running eslint --fix will even change your "let"s to "const"s where appropriate, but don't quote me on that.