Using macro sub-properties not working in Service Apply Rules

[semmasu]

Expected Behavior

A macro like $config.myproperty$ should be evaluated as macro

Current Behavior

A macro like $config.myproperty$ is evaluated as a string, currently only $config$ is treated as a macro

Possible Solution

The macro-whitelist could be implemented as a regex-pattern instead of plain string. This way instead of whitelisting array(['config']) it could be whitelisted as something like array(['^config[.$]']) to also capure all string starting with config.

Steps to Reproduce (for bugs)

1. Create a Host with a custom variable containing an array of objects
   
2. Create a Service-Apply-Rule for this array
3. Try to use a macro for the property of the array-element (e.g: $config.host$)
4. Check the preview, config.host is surrounden by "

Your Environment

• Director version (System - About): 1.7.2 (master Feb 12, 2020)
• Icinga Web 2 version and modules (System - About): 2.7.3
• Icinga 2 version (icinga2 --version): r2.11.2-1
• Operating System and version: Ubuntu 18.04.4 LTS (Bionic Beaver)
• Webserver, PHP versions: apache/2.4.41