The current mvn-scm-provider-jgit implementation does not support the explicit use of public key auth. The underlying implementation implicitly uses ~/id_rsa or ~/id_dsa if present (and not protected by a passphrase).
For most Git repositories (Github, Gitlab, ...), public key authentication is mandatory for ssh access.
This forces users to either use https, or to rely on a unprotected private key file.
maven-scm-provider-jgit should support the privateKey and passphrase attributes available in server entries in maven settings.xml for ssh URLs