LAKITU: force rebuild of grub

The previous change (commit 28d0077160f790ce8292c00a2530c7cda2c4cc7d)
didn't uprev the grub ebuild. As a result, it's not being picked up
in developer chroots or in builders.

BUG=b/257271340
TEST=presubmit
RELEASE_NOTE=None

Change-Id: I4691394638e55212e50512b8075f5b0ed374d211
Reviewed-on: https://cos-review.googlesource.com/c/third_party/overlays/chromiumos-overlay/+/41356
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
diff --git a/sys-boot/grub/grub-2.06-r9.ebuild b/sys-boot/grub/grub-2.06-r10.ebuild
similarity index 100%
rename from sys-boot/grub/grub-2.06-r9.ebuild
rename to sys-boot/grub/grub-2.06-r10.ebuild