2023-01-22 Pi-hole admin password changes - experimental branch - PR 3 of 3

[Paraphraser]

…3 of 3

See #648 for background to this PR.

Consequential changes:

• harmonises template service definition by removing reference to port 443 and re-aligning entries.
• harmonises default environment variables to be the same as master branch (including comments).
• removes obsolete networks: clause.
• removes handling for TZ, WEBPASSWORD, DNS1 and DNS2 from the modifiable environment. The DNS pair are a consequence of overall harmonisation.

Signed-off-by: Phill Kelley 34226495+Paraphraser@users.noreply.github.com