[gimp-help] Small typo fixed

[Marco Ciampa <marcoc src gnome org>]

commit b295b179a2df64727f552d8594df981fab434db3
Author: Marco Ciampa <ciampix posteo net>
Date:   Wed Sep 4 13:56:30 2019 +0200

    Small typo fixed

 src/filters/light-and-shadow/drop-shadow-legacy.xml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/filters/light-and-shadow/drop-shadow-legacy.xml 
b/src/filters/light-and-shadow/drop-shadow-legacy.xml
index ba26ab08b..183084f5b 100644
--- a/src/filters/light-and-shadow/drop-shadow-legacy.xml
+++ b/src/filters/light-and-shadow/drop-shadow-legacy.xml
@@ -10,10 +10,10 @@
   <indexterm>
     <primary>Filters</primary>
     <secondary>Light and Shadow</secondary>
-    <tertiary>Drop Shadow (legacy></tertiary>
+    <tertiary>Drop Shadow (legacy)</tertiary>
   </indexterm>
   <indexterm>
-    <primary>Drop Shadow (legacy></primary>
+    <primary>Drop Shadow (legacy)</primary>
   </indexterm>
 
   <sect3>