Tools: Adapt proxylistener to eqiad naming scheme

In eqiad, tool accounts are now named "tools.TOOL", and there are
precautions in place that user accounts cannot be named in this way.

Bug: 62961
Change-Id: Iaa44f442a10ad1c65bf4e33255ce2093f98cb12a
Merge "Tools: Adapt proxylistener to eqiad naming scheme" into production