Disable the "Press ESCAPE for boot options" prompt in arm64

We can improve provisioning times form arm64 VMs by few seconds by
setting the timeout for this prompt to 0. Default was 3.

This timeout is already 0 for x64.

build-edk2

@@ -104,6 +104,8 @@ build_edk2() {
             build -a X64 -t GCC5 -p OvmfPkg/CloudHv/CloudHvX64.dsc -b RELEASE -n 0
             cp Build/CloudHvX64/RELEASE_GCC5/FV/CLOUDHV.fd "$WORKLOADS_DIR/CLOUDHV-x64.fd"
         elif [ "$architecture" = "aarch64" ]; then
+            # We don't need the "Press ESCAPE for boot options" prompt
+            sed -i 's/\(gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|\)[0-9]\+/\10/g' edk2_build/edk2/ArmVirtPkg/ArmVirtCloudHv.dsc
             build -a AARCH64 -t GCC5 -p ArmVirtPkg/ArmVirtCloudHv.dsc -b RELEASE -n 0
             cp Build/ArmVirtCloudHv-AARCH64/RELEASE_GCC5/FV/CLOUDHV_EFI.fd "$WORKLOADS_DIR/CLOUDHV-arm64.fd"
         else