Add open_browser param to auth prompts

[sventec]

This PR adds an open_browser parameter to both auth prompt functions. This is intended to behave similarly to the option in spotipy (ref 2), allowing for interactive auth without an attempt to open the system default browser.

This beneficial in some instances where opening the default browser could be abrupt to the user; I sometimes find manually pasting the link into my currently open browser helpful, as e.g. my system default browser is not open at the time, or I am using WSL, a VM, a container, etc. from which the relevant auth code is being invoked.

The open_browser param has a default value of True, so as to not modify the existing default behavior.

Related issue: None

• Tests written with 100% coverage
  • N/A
• Documentation and changelog entry written
• All tox checks passed with an appropriately configured
  environment

[felix-hilden]

Beautiful 👌 could you write a changelog entry under a new "unreleased" header too?

[sventec]

@felix-hilden oops, thanks for the reminder. release notes have been updated!

[felix-hilden]

Thanks! This needs to run some live tests so the PR will fail, I'll try to merge it in in the coming days and run the tests for real 👍