Update api version to 1.2.0

In the node endpoint the version field has been renamed to agent

config/default.json

@@ -1,7 +1,7 @@
 {
   "nodes": {
     "fallbackPublicExplorer": "https://app.radicle.xyz/nodes/$host/$rid$path",
-    "apiVersion": "1.1.0",
+    "apiVersion": "1.2.0",
     "defaultHttpdPort": 443,
     "defaultLocalHttpdPort": 8080,
     "defaultHttpdHostname": "seed.radicle.garden",

radicle-httpd/src/api.rs

@@ -36,7 +36,7 @@ use crate::Options;
 
 pub const RADICLE_VERSION: &str = env!("RADICLE_VERSION");
 // This version has to be updated on every breaking change to the radicle-httpd API.
-pub const API_VERSION: &str = "1.1.0";
+pub const API_VERSION: &str = "1.2.0";
 
 /// Identifier for sessions
 type SessionId = String;