d/t/local-resolve-service: Add non-superficial DEP-8 test

Add a non-superficial DEP-8 test, which validates resolving of mDNS .local domains and service discovery.

SalsaCI shows:

autopkgtest [09:53:12]: Setting up user "debci" to sudo without password...
autopkgtest [09:53:12]: test local-resolve-service: [-----------------------
Server version: avahi 0.8; Host name: ci-079-58a9cf64.local
ci-079-58a9cf64.local	10.0.3.254
Server version: avahi 0.8; Host name: ci-079-58a9cf64.local
Address:   10.0.3.254           00001010.00000000.00000011. 11111110
Server version: avahi 0.8; Host name: ci-079-58a9cf64.local
ci-079-58a9cf64.local	fe80::216:3eff:feba:af85
Server version: avahi 0.8; Host name: ci-079-58a9cf64.local
Address: fe80::216:3eff:feba:af85                1111111010000000:0000000000000000:0000000000000000:0000000000000000:0000001000010110:0011111011111111:1111111010111010:1010111110000101
<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
  <name replace-wildcards="yes">%h Dummy</name>
  <service>
    <type>_dummy._tcp</type>
    <port>4242</port>
    <txt-record>Autopkgtest dummy</txt-record>
  </service>
</service-group>
   hostname = [ci-079-58a9cf64.local]
   hostname = [ci-079-58a9cf64.local]
   hostname = [ci-079-58a9cf64.local]
   address = [fe80::216:3eff:feba:af85]
   address = [10.0.3.254]
   port = [4242]
   port = [4242]
   port = [4242]
   txt = ["Autopkgtest dummy"]
   txt = ["Autopkgtest dummy"]
   txt = ["Autopkgtest dummy"]
autopkgtest [09:53:14]: test local-resolve-service: -----------------------]
local-resolve-service PASS