removed unnecessary validate; automatic on tofile()

Author: Kyle A Logue

tests/test_ncd.py

@@ -47,7 +47,6 @@ def test_load_ncd(self, subdir: str) -> None:
         # create metadata file
         ncd_metadata = copy.deepcopy(TEST_METADATA)
         meta = SigMFFile(metadata=ncd_metadata, data_file=data_path)
-        meta.validate()
         meta.tofile(meta_path)
 
         # load dataset & validate we can read all the data