[gnome-calendar] window: Add missing keyboard shortcut

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

commit 19ee70f9aba4b025da85c7079f9bd02056cd37df
Author: Rajat Jain <rajatjain ix gmail com>
Date:   Mon Apr 19 01:10:00 2021 +0530

    window: Add missing keyboard shortcut
    
    Add missing accelerator for <Alt>+Down as it was
    mentioned in shortcuts dialog but not implemented.
    
    Fixes #492
    
    Signed-off-by: Rajat Jain <rajatjain ix gmail com>

 src/gui/gcal-window.ui | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/gui/gcal-window.ui b/src/gui/gcal-window.ui
index 21370952..46ea361a 100644
--- a/src/gui/gcal-window.ui
+++ b/src/gui/gcal-window.ui
@@ -193,6 +193,7 @@
                 <property name="receives_default">True</property>
                 <property name="action-name">win.today</property>
                 <accelerator key="t" modifiers="GDK_CONTROL_MASK" signal="clicked"/>
+                <accelerator key="Down" modifiers="GDK_MOD1_MASK" signal="clicked"/>
                 <accelerator key="Home" signal="clicked"/>
               </object>
             </child>