Update release repository pin

Change-Id: I679b66b97d0e32a5b39c2a53944c00743106dc82
Signed-off-by: morgolock <pablo.tello@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/4529
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Tested-by: Michele Di Giorgio <michele.digiorgio@arm.com>

diff --git a/release_repository b/release_repository
new file mode 160000 (submodule)
index 0000000..18b685f
--- /dev/null
+++ b/release_repository
@@ -0,0 +1 @@
+Subproject commit 18b685f5d09ba07aa54e050f881a0befe3e36047