Get rid of Apache AvailablePortFinder

[sfionov]

Binding to port 0 is more reliable in any cases. Also, current implementation keeps open socket at port 1100.

But support of binding to port 0 requires API methods to retrieve port to which server was bound.

Linked CoreLibs issue:
AdguardTeam/CoreLibs#1028

[admitrevskiy]

Done.

Testing instructions for QA:

• Reinstall AG
• Examine possible protection restart cases for different filtering methods and configurations