remove previous exception interpolation from raised exception

Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>

Author: maxisbey

src/mcp/server/mcpserver/prompts/base.py

@@ -210,4 +210,4 @@ async def render(
         except MCPError:
             raise
         except Exception as exc:
-            raise ValueError(f"Error rendering prompt {self.name}: {exc}") from exc
+            raise ValueError(f"Error rendering prompt {self.name}) from exc