Building container images fails because Wheezy moved to archive.debian.org

Trying to run "make nightly-linux-x86_64" in the "tor-browser-build" repo fails with errors relating to 404 HTTP status codes on deb.debian.org. (If you've already built Tor Browser before the move, then reproducing this error probably requires that you make a change to a project's apt-get dependencies so that rbm tries to build a new container image, or else deleting a container image so that rbm needs to build it again.) This happens because Wheezy was recently moved to archive.debian.org.