[COMPLIANCE] Add Copyright and License Headers (#17732)

Co-authored-by: hashicorp-copywrite[bot] <110428419+hashicorp-copywrite[bot]@users.noreply.github.com>

e2e/isolation/doc.go

@@ -1,3 +1,6 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
 // Package isolation provides tests around various kinds of isolation, such as
 // artifact downloading, PID namespacing, and chroot task environments.
 package isolation

scripts/docker-entrypoint.sh

@@ -1,4 +1,7 @@
 #!/usr/bin/env ash
+# Copyright (c) HashiCorp, Inc.
+# SPDX-License-Identifier: MPL-2.0
+
 
 case "$1" in
   "agent" )