[gtksourceview] testdark.xml: add search-match for tests

[Christian Hergert <chergert src gnome org>]

commit 365175c827dbab19992e43caf454980ea876c78c
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jan 6 18:32:55 2022 -0800

    testdark.xml: add search-match for tests
    
    Related #244

 data/styles/testdark.xml | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/data/styles/testdark.xml b/data/styles/testdark.xml
index ee8f9e5c..36fcf6cf 100644
--- a/data/styles/testdark.xml
+++ b/data/styles/testdark.xml
@@ -15,4 +15,5 @@
   <style name="current-line"        background="gray"/>
   <style name="line-numbers"        foreground="#FFFF00" background="#006400"/>
   <style name="current-line"        background="#90EE90"/>
+  <style name="search-match"        background="magenta"/>
 </style-scheme>