Invoke DwmFlush() before acquiring the next frame to alleviate visual stutter
during mouse movement at the cost of constraining the capture rate to the host's
monitor refresh.
Disabled by default; enable via "dwmflush" boolean configuration parameter.
- remove ubuntu 21.04 from CI (end of life)
- adjust matrix strategy for clang.yml
- Use lessons learned from RetroArcher on localize.yml, crowdin.yml, and locale.py
- Add end of life comments to Dockerfiles
- Adjust dependency order in Dockerfiles
