v2.9.1-rc.1

Security

• CVE-2021-40403: Gerbv pick-and-place rotation parsing use of uninitialized variable vulnerability, discovered by @CiscoTalos team in issue #82, fixed by @ooxi in PR#85

ci

• Use latest Ubuntu LTS for website generation (PR#118 by @ooxi)
• Use latest Fedora release for Windows cross compilation (PR#117 by @ooxi)
• Update to Fedora 36 in CI (PR#116 by @ooxi)
• Update to Ubuntu 22.04 in CI (PR#114 by @ooxi)