Warning when vsmdi files are passed in.

[AbhitejJohn]

Description

The adapter currently throws the following warning when a vsmdi file is passed to it:
"A testsettings file or a runsettings with a ForcedLegacyMode set to true is not supported with the MSTest V2 Adapter."
This does not indicate that this is an unsupported scenario.

Steps to reproduce

1. unzip the mstestv2 project from the attachments.
2. Discover tests.
3. Ensure that the test settings via the Test-> TestSettings is pointing to a vsmdi file.
4. Discover Tests

Expected behavior

A warning that indicates this is an unsupported behavior.

Actual behavior

The following warning shows up: "A testsettings file or a runsettings with a ForcedLegacyMode set to true is not supported with the MSTest V2 Adapter."

Repro.zip

[pvlakshm]

This should be fixed.

[pvlakshm]

Validate and close, please.