Remove no-std-check/src/lib.rs from rustfmt exclusion list

.. now continously checking its formatting in CI.

Author: tnull

rustfmt_excluded_files

@@ -261,4 +261,3 @@
 ./lightning/src/util/time.rs
 ./lightning/src/util/transaction_utils.rs
 ./lightning/src/util/wakers.rs
-./no-std-check/src/lib.rs