update to proxmox-sys 0.2 crate

- imported pbs-api-types/src/common_regex.rs from old proxmox crate
- use hex crate to generate/parse hex digest
- remove all reference to proxmox crate (use proxmox-sys and
  proxmox-serde instead)

Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>

pbs-tape/src/sg_tape/mam.rs

@@ -175,7 +175,7 @@ fn decode_mam_attributes(data: &[u8]) -> Result<Vec<MamAttribute>, Error> {
                             unreachable!();
                         }
                     },
-                    MamFormat::BINARY => proxmox::tools::digest_to_hex(&data),
+                    MamFormat::BINARY => hex::encode(&data),
                 };
                 list.push(MamAttribute {
                     id: head_id,