Fix pulse cookie encoding

[futpib]

After reboot paclient would connect without an issue, but if I killed pulseaudio (and let it restart), then paclient would not connect. I noticed hex encoding was used when working with cookies, but ascii was used when reading, so I switched it to hex. This fixed the connection issue for me.

[gu3st]

This fixed my connection problems with Pulse. Mergin this would be good.