[gnome-control-center] docs: Remove trailing space from code example

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit a4746a90c74b48ce430a1532561791e4ac8b4296
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Tue Jun 19 16:29:04 2018 +0000

    docs: Remove trailing space from code example

 docs/HACKING.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/docs/HACKING.md b/docs/HACKING.md
index 8983e962a..a60e20636 100644
--- a/docs/HACKING.md
+++ b/docs/HACKING.md
@@ -43,7 +43,7 @@ if (a || b || (c && d))
   return;
 
 // Multiline if with nested parenthesis
-if (long_boolean_variable_used_in_this_condition_a || 
+if (long_boolean_variable_used_in_this_condition_a ||
     long_boolean_variable_used_in_this_condition_b ||
     (long_boolean_variable_used_in_this_condition_c &&
      long_boolean_variable_used_in_this_condition_d))