We had a hardcoded assumption that the SSH user for a Git repository is
always "git". This is however not true in all scenarios, for example
when one is making use of Gerrit for team code collaboration, as users
there have their own username for (SSH) Git operations.
This commit changes the logic of the auth strategy helpers to:
1. Select the auth strategy based on the protocol of the parsed URL,
instead of a simple rely on a correct prefix.
2. Use the user information from the parsed URL to configure the user
for the public key authentication strategy, with a fallback to `git`
if none is defined.
Signed-off-by: Hidde Beydals <hello@hidde.co>
As this will result in a checkout failure when the default branch on the
remote is not `master`. Surfaced due to Contour switching from `master` to
`main` overnight.