import-puppet-module: Make script more resilient when failure occurs

• New repository can use other branch name than 'master', so now we can provide that

name (e.g. 'main')

• When issues happen when importing the repository for the first time, it becomes

difficult to try again without having to tamper with the forge. So this now allows to
pass along flags to make multiple calls eventually work without having to do everything
from scratch [1]

[1] Example call:

python bin/import-puppet-module \
  --default-branch main \
  --repo-id 257 \
  --no-clone \
  puppetlabs-zfs_core

Related to T4102