fix: wrong pico_service password + picodata expel --user

Summary

• fix: used to not provide pico_service password on initial replication configuration
• test: now conftest.Cluster.deploy sets the non-empty pico_service password for the cluster
• fix: picodata expel now accepts --user, --password-file & --auth-method parameters and behaves the same way picodata connect does with respect to credentials

Note that using picodata expel requires providing a user which is authorized to execute stored procedure .proc_expel_redirect. Currently by default the only such user is pico_service and the only way to create another user with such privileges is to go through lua.

---

• Close #...
• Target branch: master
• Changes should be cherry-picked to 24.1: yes / no
• Docs follow-up: docs#199 (closed)

src/traft/error.rs

@@ -22,7 +22,7 @@ pub enum Error {
         actual: &'static str,
     },
     /// cluster_id of the joining instance mismatches the cluster_id of the cluster
-    #[error("cannot join the instance to the cluster: cluster_id mismatch: cluster_id of the instance = {instance_cluster_id:?}, cluster_id of the cluster = {cluster_cluster_id:?}")]
+    #[error("cluster_id mismatch: cluster_id of the instance = {instance_cluster_id:?}, cluster_id of the cluster = {cluster_cluster_id:?}")]
     ClusterIdMismatch {
         instance_cluster_id: String,
         cluster_cluster_id: String,