[3.2.x] Fixed #34756 -- Fixed docs HTML build on Sphinx 7.1+.

Backport of b3e0170 from main

docs/_ext/djangodocs.py

@@ -130,10 +130,23 @@ def depart_table(self, node):
 
     def visit_desc_parameterlist(self, node):
         self.body.append('(')  # by default sphinx puts <big> around the "("
-        self.first_param = 1
         self.optional_param_level = 0
         self.param_separator = node.child_text_separator
-        self.required_params_left = sum(isinstance(c, addnodes.desc_parameter) for c in node.children)
+        # Counts 'parameter groups' being either a required parameter, or a set
+        # of contiguous optional ones.
+        required_params = [
+            isinstance(c, addnodes.desc_parameter) for c in node.children
+        ]
+        # How many required parameters are left.
+        self.required_params_left = sum(required_params)
+        if sphinx_version < (7, 1):
+            self.first_param = 1
+        else:
+            self.is_first_param = True
+            self.params_left_at_level = 0
+            self.param_group_index = 0
+            self.list_is_required_param = required_params
+            self.multi_line_parameter_list = False
 
     def depart_desc_parameterlist(self, node):
         self.body.append(')')