tape/inventory: fix the tape tests as user, by mocking the lock

locking during the tests as regular user failed because we try to
chown to the backup user (which is not always possible).

Instead, do not lock at all, by implementing 'open_backup_lockfile' with
'create_mocked_lock'

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/tape/inventory.rs

@@ -40,7 +40,20 @@ use proxmox::tools::{
 };
 
 use pbs_systemd::time::compute_next_event;
-use pbs_config::{open_backup_lockfile, BackupLockGuard};
+use pbs_config::BackupLockGuard;
+
+#[cfg(not(test))]
+use pbs_config::open_backup_lockfile;
+
+#[cfg(test)]
+fn open_backup_lockfile<P: AsRef<std::path::Path>>(
+    _path: P,
+    _timeout: Option<std::time::Duration>,
+    _exclusive: bool,
+) -> Result<pbs_config::BackupLockGuard, anyhow::Error> {
+    Ok(unsafe { pbs_config::create_mocked_lock() })
+}
+
 
 use crate::{
     api2::types::{