Add new env variables for new doh config keys

[satishweb]

Ref: https://github.com/m13253/dns-over-https/issues/167#issuecomment-2644049726

Add new variables for below doh server config keys:

log_guessed_client_ip
ecs_allow_non_global_ip
ecs_use_precise_ip
tls_client_auth
tls_client_auth_ca
local_addr
cert
key