lsp_plugin: remove reserve from hook response

This slipped in during development but actually, we don't want to mess
with the channel reservere here.

Signed-off-by: Peter Neuroth <pet.v.ne@gmail.com>

Author: nepet

plugins/lsps-plugin/src/client.rs

@@ -540,7 +540,6 @@ async fn on_openchannel(
         // found in the ds record.
         return Ok(serde_json::json!({
             "result": "continue",
-            "reserve": "0msat",
             "mindepth": 0,
         }));
     } else {