tor-hsservice: Use real HsNickname in config

crates/tor-hsservice/src/config.rs

@@ -1,18 +1,18 @@
 //! Configuration information for onion services.
 
+use crate::HsNickname;
+
 /// Configuration for a single onion service.
 #[derive(Debug, Clone)]
 pub struct OnionServiceConfig {
-    /// An arbitrary identifier or "nickname" used to look up this service's
-    /// keys, state, configuration, etc,
-    /// and distinguish them from other services.  This is local-only.
+    /// The nickname used to look up this service's keys, state, configuration, etc,
     //
     // TODO HSS: It's possible that instead of having this be _part_ of the
     // service's configuration, we want this to be the key for a map in
     // which the service's configuration is stored.  We'll see how the code
     // evolves.
     // (^ ipt_mgr::IptManager contains a copy of this nickname, that should be fixed too)
-    nickname: String,
+    nickname: HsNickname,
 
     /// Whether we want this to be a non-anonymous "single onion service".
     /// We could skip this in v1.  We should make sure that our state