fix(challenges): Add whitespace check to regex

[RobAnthony01]

Add \/\s*? to start of looked for code and \s*?\/ after semi colon.
This traps any extra non-whitespace between the comments.

Description

The tests could still pass if additional text was put between the comments on the solution.
This checks to make sure ONLY whitespace and the correct solution is between the comments.

Pre-Submission Checklist

• Your pull request targets the dev branch.
• Branch starts with either fix/, feature/, or translate/ (e.g. fix/challenge-tests)
• All new and existing tests pass the command npm test.
• Use npm run commit to generate a conventional commit message.
  Learn more here: https://conventionalcommits.org/#why-use-conventional-commits
• The changes were done locally on your machine and NOT GitHub web interface.
  If they were done on the web interface you have ensured that you are creating conventional commit messages.

Checklist:

• Tested changes locally.
• Addressed currently open issue (replace XXXXX with an issue no in next line)

Closes #228