Merge the Tails sysadmins and TPA password stores

ref: https://gitlab.torproject.org/tpo/tpa/team/-/wikis/policy/tpa-rfc-73-tails-infra-merge-roadmap#password-store

• Map passwords between repos
• Wait for the "check compliance of TPA members to Tail's security policy, level B (which includes level A)," step in tpo/tpa/team#41727
• Move passwords
• Update doc
• Archive obsolete repo
• Inform in mailing list