[heads-up] evolution-data-server is libsoup3 now

[Milan Crha <mcrha redhat com>]

        Hello,
just a quick heads-up, the evolution-data-server development version is
libsoup3 now; it will be the 3.45.1 release. The port depends on
libsoup3 change [1], which improves libsoup3 use in multi-threaded
applications.

Most people are probably aware, all apps using the evolution-data-
server directly or indirectly need to use libsoup3 as well, the same
their dependencies, because libsoup2 and libsoup3 cannot be loaded into
the same process at the same time (doing so aborts the application with
an appropriate message).

One thing, the libgdata has a pending merge request for the port to the
libsoup3, but it needs more testing and such.
Use -DENABLE_GOOGLE=OFF CMake option until it's sorted out. The option
disables the Google tasks support only. I may extract necessary bits
out of the libgdata to not depend on libgdata at all, but no promises
whether I'll make it on time for the 3.45.1. See [2] for some insights.

Of course, Evolution itself and evolution-ews will be ported to the
libsoup3 at the same time.

        Bye,
        Milan

[1] https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/283
[2] https://discourse.gnome.org/t/giving-up-maintainership-of-libgdata/9983