Add pypubsub to AppImageBuilder. #242

Job	Run time
Build & Release (ubuntu-24.04, pyinstaller BindControl.spec, ls -la dist/BindControl, --symlinks,...	2m 14s
Build & Release (windows-latest, pyinstaller BindControl.spec, dir dist/BindControl, echo, BindCo...	1m 16s
Build & Release (macos-15-intel, pyinstaller BindControl.spec, ls -la dist/BindControl.app, rm -r...	1m 28s
Build & Release (macos-15, pyinstaller BindControl.spec, ls -la dist/BindControl.app, rm -rf dist...	36s
	5m 34s

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