Revert "update to use containerd seccomp package"

This reverts commit 4f8e065faf055d3f0463a92622297ca3afac07f4.

vendor/github.com/docker/cli/scripts/warn-outside-container

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+set -eu
+
+target="${1:-}"
+
+if [[ -z "${DISABLE_WARN_OUTSIDE_CONTAINER:-}" ]]; then
+    (
+        echo
+        echo
+        echo "WARNING: you are not in a container."
+        echo "Use \"make -f docker.Makefile $target\" or set"
+        echo "DISABLE_WARN_OUTSIDE_CONTAINER=1 to disable this warning."
+        echo
+        echo "Press Ctrl+C now to abort."
+        echo
+    ) >&2
+    sleep 10
+fi