add charset_normalizer as dependency

setup.cfg

@@ -8,28 +8,29 @@ long_description = file: README.md
 long_description_content_type = text/markdown
 license = MIT
 url = https://github.com/XraySpectroscopy/pynxxas/
-project_urls = 
+project_urls =
     Source = https://github.com/XraySpectroscopy/pynxxas/
     Documentation = https://pynxxas.readthedocs.io/
     Tracker = https://github.com/XraySpectroscopy/pynxxas/issues/
-classifiers = 
+classifiers =
     Intended Audience :: Science/Research
     License :: OSI Approved :: MIT License
     Programming Language :: Python :: 3
 
 [options]
 package_dir=
-	=src
+        =src
 packages=find:
 python_requires = >=3.8
-install_requires = 
+install_requires =
     typing_extensions; python_version < "3.9"
     strenum; python_version < "3.11"
     numpy
     h5py
     pydantic >=2.6
     pint
     periodictable
+    charset_normalizer
 
 [options.packages.find]
 where=src
@@ -56,7 +57,7 @@ console_scripts =
 [flake8]
 ignore = E501, E203, W503
 max-line-length = 88
-exclude = 
+exclude =
     .eggs
 
 # E402 (module import not at top of file) ignored