Remove redundant --group dev flag from uv sync

The dev group is already specified as a default group in pyproject.toml,
so uv sync automatically includes it without the explicit flag.

Author: SmileyChris

README.md

@@ -116,8 +116,8 @@ graphql_op='getUserProfile' - 2 queries (optimized)
 Contributions welcome! Please see our issues and discussions.
 
 ```bash
-# Install with dev dependencies
-uv sync --group dev
+# Install dependencies
+uv sync
 
 # Run tests
 just test