Fixing Basic 12 Ns Primitives

NSD folder name can be different than the NSD package name.
Getting the exact NSD folder name while finding charm name.
Removing redefined the method async def upgrade_charm causing flake8 error.

Change-Id: I772c6a47104271de0a18c748d380ed71849194f0
Signed-off-by: aticig <gulsum.atici@canonical.com>