bitrise update doesn't work when installed via source

[f1047]

Symptoms:

• When executing bitrise update:

  Updating Bitrise CLI...
  Current version: 2.31.0
  Bitrise CLI installed from source
  Updating to version: 2.31.1
  Downloading Bitrise CLI...
  Update Bitrise CLI failed, error: can't download url (https://github.com/bitrise-io/bitrise/releases/download/2.31.1/bitrise-Darwin-x86_64), status: Not Found
  

When I use bitrise update --version v2.31.1, it passes.

I think the URL link to the release should be tweaked. Could it be the spec changes on GitHub? (I don't have any evidence, though.)

[lpusok]

Thank you. It seems we changed the version format (added a v prefix), but possible did not update something to match.