CI: The-no-space-left-on-device-quest: Enforce disabled ccache support and don't strip vmlinux

The late strip seems to be where it breaks on each run. Let's try without.

.github/workflows/build-current-kernel-arch.yml

@@ -10,6 +10,8 @@ env:
   _processor_opt: "generic"
   PKGDEST: "/tmp/linux-tkg"
   _debugdisable: "true"
+  _noccache: "true"
+  _STRIP: "false"
   #_kernel_work_folder: "/tmp"
   #_kernel_source_folder: "/tmp"
   # _modprobeddb: "true"