Match selector passes on missing field

[BernieWhite]

Description of the issue

The match selector expression passes if the specified field does not exist.

Expected behaviour

The expression should only pass if the field exists and matches the regular expression.

Module in use and version:

• Module: PSRule
• Version: 1.5.0-B2106006

Captured output from $PSVersionTable:

Name                           Value
----                           -----
PSVersion                      7.1.3
PSEdition                      Core
GitCommitId                    7.1.3
OS                             Microsoft Windows 10.0.19043
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0