Bump pyvirtualdisplay from 0.2.1 to 0.2.3
Bump pyvirtualdisplay from 0.2.1 to 0.2.3

Bumps [pyvirtualdisplay](https://github.com/ponty/pyvirtualdisplay) from 0.2.1 to 0.2.3.
- [Release notes](https://github.com/ponty/pyvirtualdisplay/releases)
- [Commits](https://github.com/ponty/pyvirtualdisplay/compare/0.2.1...0.2.3)
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