WORKSPACE: bump kernel to 5.15.104

Bumps the kernel to the latest patch release.

Hash verified against GPG signature from
647F28654894E3BD457199BE38DBBDC86092693E alias Greg KH.

Change-Id: I20d78d0492d1e869d684a1c045341f142f2039c8
Reviewed-on: https://review.monogon.dev/c/monogon/+/1410
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
diff --git a/WORKSPACE b/WORKSPACE
index 17d438b..398622a 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -129,7 +129,7 @@
 
 linux_external(
     name = "linux",
-    version = "5.15.32",
+    version = "5.15.104",
 )
 
 load("//third_party/linux-firmware:external.bzl", "linux_firmware_external")