Update uvh5.py, pyuvdata throws error when converting to MS in prev. version

[joesbright]

Error from pyuvdata is:

File "/mnt/buf0/jbright/BLRI_STAMP/uvh52ms.py", line 8, in
uv.read(inp)
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/uvdata/uvdata.py", line 11139, in read
self.read_uvh5(
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/uvdata/uvdata.py", line 9883, in read_uvh5
uvh5_obj.read_uvh5(filename, **kwargs)
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/uvdata/uvh5.py", line 1051, in read_uvh5
self._read_header(
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/uvdata/uvh5.py", line 680, in _read_header
self._read_header_with_fast_meta(filename, **kwargs)
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/uvdata/uvh5.py", line 502, in _read_header_with_fast_meta
self.telescope = Telescope.from_hdf5(
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/telescopes.py", line 863, in from_hdf5
setattr(tel_obj, tel_attr, getattr(meta, attr))
File "/usr/lib/python3.10/functools.py", line 981, in get
val = self.func(instance)
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/pyuvdata/utils/io/hdf5.py", line 677, in antenna_names
return np.char.decode(self.header["antenna_names"][:], encoding="utf8")
File "/mnt/buf0/jbright/BLRI_STAMP/BLRI_STAMP/lib/python3.10/site-packages/numpy/_core/strings.py", line 530, in decode
vec_string(a, np.object, 'decode', _clean_args(encoding, errors)),
TypeError: string operation on non-string array

[radonnachie]

Shotalot Joe!

I'm hesitant to throw the baby out... need that "S4" string to represent the maximum string length still..
does the following work as well? If so I'd prefer it.

uvh5g_header.create_dataset("antenna_names", data=numpy.array(antenna_names).astype(f"S{max(map(len, antenna_names))}"))