Missing page title description on the home page

[nekohayo]

If you look at the home page's title in the web browser (hover the mouse on the tab to see the tooltip), you will see that it's missing some markup file to set the short description for it. We should probably reuse or adapt something from the first line(s) of the short intro text or flatpak appdata.

[Neui]

Looks like it comes from

getting-things-gnome.github.io/_config.yml

Lines 18 to 21 in e9c31e2

	description: >- # this means to ignore newlines until "baseurl:"
	Write an awesome description for your new site here. You can edit this
	line in _config.yml. It will appear in your document head meta (for
	Google search results) and in your feed.xml site description.