[gnome-mines] help: Remove another unused (and unhelpful) screenshot

[Andre Klapper <aklapper src gnome org>]

commit f6d7f871a4af04871e3ec878723f0cffc8f6f70c
Author: Andre Klapper <a9016009 gmx de>
Date:   Sat Sep 16 23:01:52 2017 +0200

    help: Remove another unused (and unhelpful) screenshot

 help/C/figures/highscores.png |  Bin 12451 -> 0 bytes
 help/Makefile.am              |    1 -
 2 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/help/Makefile.am b/help/Makefile.am
index 67dd8ab..5385cfe 100644
--- a/help/Makefile.am
+++ b/help/Makefile.am
@@ -12,7 +12,6 @@ HELP_MEDIA = \
        figures/hard-hints-1.png \
        figures/hard-hints-2.png \
        figures/hard-hints-3.png \
-       figures/highscores.png \
        figures/logo32.png \
        figures/logo.png \
        figures/main-window.png \