Update Debian kernel to v6.2.8

.github/workflows/debian.yml

@@ -7,7 +7,7 @@ name: Debian
 
 env:
   GPG_KEY_ID: 56C464BAAC421453
-  KERNEL_VERSION: 6.2.6
+  KERNEL_VERSION: 6.2.8
   KERNEL_REVISION: 1
   LOCALVERSION: -surface
   MAINLINE_REPO: git://git.launchpad.net/~ubuntu-kernel-test/ubuntu/+source/linux/+git/mainline-crack