Update Claude model

[johnd0e]

At the moment claude is broken.
Changes needed:

diff --git a/src/claude.py b/src/claude.py
index 19071a6..51217f3 100644
--- a/src/claude.py
+++ b/src/claude.py
@@ -101,7 +101,7 @@ class Client:
       "completion": {
         "prompt": f"{prompt}",
         "timezone": "Europe/London",
-        "model": "claude-2"
+        "model": "claude-2.1"
       },
       "organization_uuid": f"{self.organization_id}",
       "conversation_uuid": f"{conversation_id}",
@@ -169,7 +170,7 @@ class Client:
       "completion": {
         "prompt": f"{prompt}",
         "timezone": "Europe/London",
-        "model": "claude-2"
+        "model": "claude-2.1"
       },
       "organization_uuid": f"{self.organization_id}",
       "conversation_uuid": f"{conversation_id}",

But.. better use constant, or common func.