Update the wallpaper even if the image file already exists

.local/bin/get-nasa-apod

@@ -23,9 +23,7 @@ outfile="${WALLPAPERS}/${filename}"
 
 if [ -f "${outfile}" ]; then
     echo "Target file already exists"
-    exit 0
-fi
-
+else
     tempfile="$(mktemp)"
     curl \
         --location \
@@ -33,6 +31,8 @@ curl \
         --silent \
         "${picture_url}"
     mv "${tempfile}" "${outfile}"
+fi
+
 ln \
     --force \
     --symbolic \