This is only for jammy or newer, and it just bypass any custom ppa logic in add-apt-repository by passing -S if the source line starts with deb.
fixes #770
Take this as an idea on a possible fix, I'm far from an expert on charmhelper internals and this also requires some tests.
We are using this in our code to work around the issue.
This is only for jammy or newer, and it just bypass any custom ppa logic in add-apt-repository by passing
-S
if the source line starts with deb. fixes #770