Fix OS migration bug

[ipetrov117]

closes: #93

With the new suseconnect-ng version, we can now utilise the --gpg-auto-import-keys flag of the zypper migration command.

This means that:

1. We no longer need the gpgRepoPath property, as with --gpg-auto-import-keys flag we automatically import the key
2. Third-party repositories are added automatically as well which closes Migration fails on repo metadata errors #93.

Examples with new functionality, where the node has the following third-party repositories:

zypper ar https://download.opensuse.org/repositories/SUSE:/CA/SLE_15_SP5 opensuse-ca
zypper ar https://download.nvidia.com/suse/sle15sp5/ nvidia

Automatically imported repo keys for the 6.0 SL Micro repo + nvidia and opensuse-ca:

Retrieving repository 'SL-Micro-6.0-Pool' metadata [......

Automatically importing the following key:

  Repository:       SL-Micro-6.0-Pool
  Key Fingerprint:  1C59 D66F CD52 563A 1693 3DBC FEC2 8EAF 09D9 EA69
  Key Name:         ALP Package Signing Key <[email protected]>
  Key Algorithm:    RSA 4096
  Key Created:      Wed May 10 13:19:10 2023
  Key Expires:      Sun May  9 13:19:10 2027
  Rpm Name:         gpg-pubkey-09d9ea69-645b99ce



    Note: A GPG pubkey is clearly identified by its fingerprint. Do not rely on the key's name. If
    you are not sure whether the presented key is authentic, ask the repository provider or check
    their web site. Many providers maintain a web page showing the fingerprints of the GPG keys they
    are using.
............done]
Forcing building of repository cache
Building repository 'SL-Micro-6.0-Pool' cache [....done]
Forcing raw metadata refresh
Retrieving repository 'nvidia' metadata [....

Automatically importing the following key:

  Repository:       nvidia
  Key Fingerprint:  2FB0 3195 DECD 4949 2BD1 C17A B1D0 D788 DB27 FD5A
  Key Name:         NVIDIA Linux Driver Team <[email protected]>
  Key Algorithm:    RSA 4096
  Key Created:      Thu Apr 14 22:04:01 2022
  Key Expires:      (does not expire)
  Rpm Name:         gpg-pubkey-db27fd5a-62589a51



    Note: A GPG pubkey is clearly identified by its fingerprint. Do not rely on the key's name. If
    you are not sure whether the presented key is authentic, ask the repository provider or check
    their web site. Many providers maintain a web page showing the fingerprints of the GPG keys they
    are using.
..done]
Forcing building of repository cache
Building repository 'nvidia' cache [....done]
Forcing raw metadata refresh
Retrieving repository 'opensuse-ca' metadata [...........

Automatically importing the following key:

  Repository:       opensuse-ca
  Key Fingerprint:  511A C9AC EC2F 2372 BBBE E05D 1B99 3C94 1BE9 1FF0
  Key Name:         SUSE:CA OBS Project <SUSE:[email protected]>
  Key Algorithm:    RSA 4096
  Key Created:      Fri Feb 24 12:52:37 2023
  Key Expires:      Sun May  4 12:52:36 2025
  Rpm Name:         gpg-pubkey-1be91ff0-63f8b315



    Note: A GPG pubkey is clearly identified by its fingerprint. Do not rely on the key's name. If
    you are not sure whether the presented key is authentic, ask the repository provider or check
    their web site. Many providers maintain a web page showing the fingerprints of the GPG keys they
    are using.
.done]
Forcing building of repository cache
Building repository 'opensuse-ca' cache [....done]
All repositories have been refreshed.