[gtksourceview] rst.lang: Substitutions can have trailing _

[Christian Hergert <chergert src gnome org>]

commit e8d75e123ff3c48d8ae5f67829e677729e7c551e
Author: Pierre Ossman <ossman cendio se>
Date:   Fri Oct 15 12:57:05 2021 +0200

    rst.lang: Substitutions can have trailing _

 data/language-specs/rst.lang | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/data/language-specs/rst.lang b/data/language-specs/rst.lang
index f2d57cfb..af7005b5 100644
--- a/data/language-specs/rst.lang
+++ b/data/language-specs/rst.lang
@@ -137,7 +137,7 @@
 
     <context id="substitution" style-ref="substitution">
       <start>(\%{legal-start})\|(?!(\s|$))</start>
-      <end>(?&lt;!\s)\|(\%{legal-end})</end>
+      <end>(?&lt;!\s)\|_?_?(\%{legal-end})</end>
     </context>
 
     <context id="literals">