fix: [myc-manage] make update fail if ``myc-manage`` repository was modified

Signed-off-by: Valentin Lab <valentin.lab@kalysto.org>

bin/myc-update

@@ -23,7 +23,7 @@ if ! [ -d "/opt/apps/myc-manage" ]; then
 else
     cd /opt/apps/myc-manage &&
     git checkout master &&
-    git pull -r
+    git pull -r || exit 1
 fi
 
 ln -sfn /opt/apps/myc-manage/bin/* /usr/local/sbin/