Upgrade to Logback 1.5.16

[snicoll]

Upgrade to Logback 1.5.13.

[snicoll]

Unfortunately this seems to have broken us, I've raised qos-ch/logback#885

[edigu]

Can confirm that 1.5.14 works as intended.

[lzysuqianqiu]

1.5.15 is out

[ali-hamza-noor]

@snicoll can I raise a PR for this?

[philwebb]

There's no need thanks @ali-hamza-noor, we have an automated process.