add autosectionlabel

Signed-off-by: nstarman <nstarman@users.noreply.github.com>

Author: nstarman

sphinx_astropy/conf/v2.py

@@ -184,6 +184,7 @@
 # ones.
 extensions = [
     'sphinx.ext.autodoc',
+    "sphinx.ext.autosectionlabel",
     'sphinx.ext.coverage',
     'sphinx.ext.inheritance_diagram',
     'sphinx.ext.intersphinx',
@@ -217,6 +218,8 @@
 # class' docstring
 numpydoc_show_class_members = False
 
+autosectionlabel_prefix_document = True
+
 autosummary_generate = True
 
 automodapi_toctreedirnm = 'api'