Fix challenge url (Challenge 43 - signal input)

[WhoisBsa]

Checklist for challenge submission

• Start your PR message with Answer:${challenge_number}

Warning:

• If you want feedback or review, you must support the project on GitHub:
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  • Create one of more challenges
  • Have many valuable contributions to the project

Alternatively, you can still submit your PR to join the list of answered challenges or to be reviewed by a community member. 🔥

[tomalaforge]

@all-contributors add @WhoisBsa for bugs

[allcontributors]

@tomalaforge

I've put up a pull request to add @WhoisBsa! 🎉