Fix missing GDExtension in-editor API reference

This commit partially reverts a change in e1ce0340b78875a864d449a5e3e38e4535e9a800
which would prevent from generating API reference for GDExtension APIs.

Fixes #78829.

editor/doc_tools.cpp

@@ -374,11 +374,6 @@ void DocTools::generate(bool p_basic_types) {
 				classes.pop_front();
 				continue;
 			}
-			if (ClassDB::get_api_type(name) != ClassDB::API_CORE && ClassDB::get_api_type(name) != ClassDB::API_EDITOR) {
-				print_verbose(vformat("Class '%s' belongs neither to core nor editor, skipping.", name));
-				classes.pop_front();
-				continue;
-			}
 
 			String cname = name;
 			// Property setters and getters do not get exposed as individual methods.