Resolves symlink escape when unarchiving by removing existing paths within the same allocation directory which can occur by writing a header that points to a symlink that lives outside of the sandbox environment. This exploit requires first compromising the Nomad client agent at the source allocation.
Ref: https://hashicorp.atlassian.net/browse/NET-10607
Ref: https://github.com/hashicorp/nomad-enterprise/pull/1725
