Remove extra check for FastAPI

Author: holtskinner

src/a2a/server/apps/jsonrpc/fastapi_app.py

@@ -58,17 +58,6 @@ def __init__(
             context_builder=context_builder,
         )
 
-        self._check_fastapi_dependency()
-
-    def _check_fastapi_dependency(self) -> None:
-        """Checks if the FastAPI package is installed.
-
-        If instead of the actual FastAPI class, a dummy implementation from
-        ./fastapi_import_helpers.py is imported, initializing FastAPI() would
-        raise ImportError.
-        """
-        _app = FastAPI()
-
     def add_routes_to_app(
         self,
         app: FastAPI,