Coq 8.20.1 is out

This minor release fixes a few bugs in Coq 8.20.0 and should otherwise
remain highly compatible with it, see the
[changelog](Recent changes — Coq 8.20.1 documentation)
for detail of bugfixes.

Coq 8.20.1 is available, along with a number of libraries,
as OPAM and Nix packages or in a Docker image.

Pierre and Guilaume, on behalf of the Coq development team