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/inline_babel_call.rs

@@ -49,7 +49,7 @@ fn name<'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: &name_end,
         }));
     let (remaining, name) = recognize(many_till(
@@ -80,7 +80,7 @@ fn header<'r, 's>(
             depth: 0,
         }))
         .with_additional_node(ContextElement::ExitMatcherNode(ExitMatcherNode {
-            class: ExitClass::Beta,
+            class: ExitClass::Gamma,
             exit_matcher: &header_end,
         }));
 
@@ -131,7 +131,7 @@ fn argument<'r, 's>(
             depth: 0,
         }))
         .with_additional_node(ContextElement::ExitMatcherNode(ExitMatcherNode {
-            class: ExitClass::Beta,
+            class: ExitClass::Gamma,
             exit_matcher: &argument_end,
         }));