Relax service app name restrictions

[stijnherreman]

What problem will this feature address?

Currently a service app name has the following restrictions:

App name supports lowercase letters, numbers, '-' and can only start and end letters, and does not support continuous '-'

I'd like to have app names ending in a number.

According to #87 (comment) the app name must be a valid hostname and test-tes-1 is not a valid hostname, but I cannot find any evidence for that.
https://datatracker.ietf.org/doc/html/rfc1912 says:

Allowable characters in a label for a host name are only ASCII
letters, digits, and the `-' character. Labels may not be all
numbers, but may have a leading digit (e.g., 3com.com). Labels must
end and begin only with a letter or digit. See [RFC 1035] and [RFC
1123]. (Labels were initially restricted in [RFC 1035] to start with
a letter, and some older hosts still reportedly have problems with
the relaxation in [RFC 1123].) Note there are some Internet
hostnames which violate this rule (411.org, 1776.com). The presence
of underscores in a label is allowed in [RFC 1033], except [RFC 1033]
is informational only and was not defining a standard. There is at
least one popular TCP/IP implementation which currently refuses to
talk to hosts named with underscores in them. It must be noted that
the language in [1035] is such that these rules are voluntary -- they
are there for those who wish to minimize problems. Note that the
rules for Internet host names also apply to hosts and addresses used
in SMTP (See RFC 821).

Describe the solution you'd like

Ideally, the app name restriction matches the RFC restriction.

Describe alternatives you've considered

Having the app name not end in a number.

Additional context

No response

Will you send a PR to implement it?

Yes, if the proposed change is approved.