Move objects to a lower exit class.

Paragraph's exit matcher which detects elements was causing the plain list parser to exit after the first item was parsed which was causing significant amounts of re-parsing.

src/parser/angle_link.rs

@@ -44,7 +44,7 @@ fn path_angle<'r, 's>(
 ) -> Res<OrgSource<'s>, OrgSource<'s>> {
     let parser_context =
         context.with_additional_node(ContextElement::ExitMatcherNode(ExitMatcherNode {
-            class: ExitClass::Beta,
+            class: ExitClass::Gamma,
             exit_matcher: &path_angle_end,
         }));