Added DEFAULT_HOP_COUNT back to client

[sirmuzz]

Client requires the DEFAULT_HOP_COUNT...rp wp rpm wpm, etc

Checklist

• [ x] I've read and followed the Contribution Guide.
• [ x] My commit messages reference affected issues and mention breaking changes if applicable.
• [ x] I've updated / wrote inline documentation for the source code affected by my changes.
• [ x] All mandatory CI checks have passed (see when Pull Request has been submitted).

What does this Pull Request do

• Re-Adds DEFAULT_HOP_COUNT back into the client.js for the other functions that require it.

[SamuelToh]

@adam-nielsen hey any chance you can accept this pull request? I think this is a show stopper for the great work you have done here.

[adam-nielsen]

My apologies, I somehow thought this PR was for the parent repo and not mine! I moved that definition in commit f1133b6, as I thought it wasn't in use, so I wonder whether it's possible to change things so that we only have a single definition rather than two?