Update the wallpaper even if the image file already exists

.local/bin/get-nasa-apod

@@ -23,16 +23,16 @@ outfile="${WALLPAPERS}/${filename}"
 
 if [ -f "${outfile}" ]; then
     echo "Target file already exists"
-    exit 0
-fi
-
-tempfile="$(mktemp)"
-curl \
+else
+    tempfile="$(mktemp)"
+    curl \
         --location \
         --output "${tempfile}" \
         --silent \
         "${picture_url}"
-mv "${tempfile}" "${outfile}"
+    mv "${tempfile}" "${outfile}"
+fi
+
 ln \
     --force \
     --symbolic \