Enabled the @typescript-eslint/no-unused-expressions eslint rule (#2014)

## Description:

- Fixes #1790
- Fixed the codebase:
- expressions short-circuiting with `&&` changed to proper `if`
statements
  - `A instanceof B;` expressions now emit warnings

## Please complete the following:
- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:
michal7952

---------

Co-authored-by: Evan <evanpelle@gmail.com>

eslint.config.js

@@ -40,7 +40,6 @@ export default [
     rules: {
       // Disable rules that would fail. The failures should be fixed, and the entries here removed.
       "@typescript-eslint/no-explicit-any": "off",
-      "@typescript-eslint/no-unused-expressions": "off",
       "no-unused-vars": "off",
     },
   },