Hi there, thanks for this very useful docker image! I have just started using it as a gateway for my application to access the Microsoft SMTP servers, but I am facing a few issues with the XOAUTH2 authentication flow. When using the sasl-xoauth2 command, msal seems to not be installed.

• I think this commit might be wrong: 9fcd02f because in the final image, the /sasl venv does not contain msal even though I am on the amd64 and arm64 arch
  • specifically in the two lines containing if [[ -z "${skip_msal}" ]];
  • I believe that it should be if [[ -n "${skip_msal}" ]]; instead
  • or rather, to be more clear, in the lines above, you might have meant to start with export skip_msal="1" and after that in the future conditions, set it to blank: 9fcd02f#diff-be313ceb7db6d4b29e4c2ed24ab1c4e82a42e4971a0e44262a2f7f4322dc3a18R43-R59

I am not sure whether I am using something wrong since these commits seem a little old and I believe you have personally been using / vetting this image in between... but let me know if you would like me to open a PR with this or to enhance the documentation about how we can use XOAUTH2 with this image! I'd be happy to do so.

Separately, I recently commented on another thread: #117 (comment), I think I will compile it here

• It seems to me that XOAUTH2_INITIAL_ACCESS_TOKEN_FILE and XOAUTH2_INITIAL_REFRESH_TOKEN_FILE are not being set