CLSA-2023-1689259392 Fix CVE(s): CVE-2021-28861

SECURITY UPDATE: Redirection vulnerability in http.server - debian/patches/CVE-2021-28861.patch: Fix an open redirection vulnerability in the http.server module when an URI path starts with // - debian/patches/expat-regression.patch: some tests were fixed - CVE-2021-28861...