Update intersphinx links

Author: bsipocz

docs/conf.py

@@ -65,10 +65,10 @@
 del intersphinx_mapping['scipy']
 del intersphinx_mapping['h5py']
 intersphinx_mapping.update({
-    'astropy': ('http://docs.astropy.org/en/stable/', None),
+    'astropy': ('https://docs.astropy.org/en/stable/', None),
     'requests': ('https://requests.kennethreitz.org/en/stable/', None),
-    'pyregion': ('http://pyregion.readthedocs.io/en/stable/', None),
-    'regions': ('http://astropy-regions.readthedocs.io/en/stable/', None),
+    'pyregion': ('https://pyregion.readthedocs.io/en/stable/', None),
+    'regions': ('https://astropy-regions.readthedocs.io/en/stable/', None),
     'mocpy': ('https://cds-astro.github.io/mocpy/', None),
     'pyvo': ('https://pyvo.readthedocs.io/en/stable/', None),
 })