...which fails as documented in
solenv/flatpak-disable-gpgconf-socketdir-test.patch, presumably because the gpg
software in org.freedesktop.Sdk//1.6 (which has e.g. "gpgconf (GnuPG)
2.1.14-unknown") doesn't shut down a started gpg daemon again.  Lets see if this
will get fixed by
<https://github.com/flathub/org.libreoffice.LibreOffice/issues/54> "Build
against org.freedesktop.Platform 18.08" (where org.freedesktop.Sdk//18.08 has
e.g. "gpgconf (GnuPG) 2.2.9").

Change-Id: I9c7ad326ff8f2278ec58ee484d088f6fba97694d