docs: Fix misplaced comment in dependency-injection.rst for better cl…

…arity (#3671)

Update dependency-injection.rst

docs/usage/dependency-injection.rst

@@ -37,9 +37,8 @@ the application:
            local_dependency: int,
        ) -> None: ...
 
-       # on the router
-
 
+   # on the router
    my_router = Router(
        path="/router",
        dependencies={"router_dependency": Provide(dict_fn)},