nginx,acme: make sensu checks work for non-HTTPS usage

[dpausp]

There are two separate Sensu checks for ACME certificate validity now:

The existing Sensu check which uses check_http is now generated per Nginx vhost when ACME is enabled. It is renamed to nginx_https_${vhost_name}. ACME.

Another Sensu check is generated for all ACME certs, using the openssl command which works in the local file system, independently of Nginx. This check has the name of the existing check ssl_cert_${cert_name}.

PL-131278

@flyingcircusio/release-managers

Release process

• Created changelog entry using ./changelog.sh

PR release workflow (internal)

• PR has internal ticket
• internal issue ID (PL-…) part of branch name
• internal issue ID mentioned in PR description text
• ticket is on Platform agile board
• ticket state set to Pull request ready
• if ticket is more urgent than within the next few days, directly contact a member of the Platform team

Design notes

• Provide a feature toggle if the change might need to be adjusted/reverted quickly depending on context. Consider whether the default should be on or off. Example: rate limiting.
• All customer-facing features and (NixOS) options need to be discoverable from documentation. Add or update relevant documentation such that hosted and guided customers can understand it as well.

Security implications

• Security requirements defined? (WHERE)
• Security requirements tested? (EVIDENCE)