Bump freesasa from 2.0.3.post7 to 2.1.0

Bumps [freesasa](https://github.com/mittinatten/freesasa) from 2.0.3.post7 to 2.1.0.
- [Release notes](https://github.com/mittinatten/freesasa/releases)
- [Changelog](https://github.com/mittinatten/freesasa/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mittinatten/freesasa/commits)

---
updated-dependencies:
- dependency-name: freesasa
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

setup.py

@@ -50,7 +50,7 @@
         'torch',
         'pdb2sql >= 0.5.0',
         'freesasa==2.0.3.post7;platform_system=="Linux"',
-        'freesasa==2.0.5;platform_system=="Darwin"'
+        'freesasa==2.1.0;platform_system=="Darwin"'
         ],
     extras_require={
         'test': ['nose', 'coverage', 'pytest', 'pytest-cov',