Add some unit tests (#321)

- Add some unit tests to the project
- These aren't massive, more just checks to ensure certain things are as they should
  - Such as checking all commands are actually registered

#15

Reviewed-on: #321
Reviewed-by: VylpesTester <tester@vylpes.com>
Co-authored-by: Ethan Lane <ethan@vylpes.com>
Co-committed-by: Ethan Lane <ethan@vylpes.com>

package.json

@@ -7,7 +7,7 @@
     "clean": "rm -rf node_modules/ dist/",
     "build": "tsc",
     "start": "node ./dist/bot.js",
-    "test": "jest --passWithNoTests",
+    "test": "jest",
     "lint": "eslint .",
     "lint:fix": "eslint . --fix",
     "db:up": "typeorm migration:run -d dist/database/dataSources/appDataSource.js",