Some `XmlReader`s in XmlRunSettingsUtilities are not disposed

[omajid]

Description

In XmlRunSettingsUtilities, we allocate various XmlReaders but don't always Diposes them

Steps to reproduce

vstest/src/Microsoft.TestPlatform.ObjectModel/Utilities/XmlRunSettingsUtilities.cs

Line 236 in 9ab8d6c

var reader = XmlReader.Create(stringReader, ReaderSettings);

This is never Dispose()d.

Expected behavior

All IDisposables are disposed.

Actual behavior

Some IDisposables are not disposed in XmlRunSettingsUtilities.

Diagnostic logs

N/A

Environment

Commit 9ab8d6c