fix more broken namespaces

[TimothyMothra]

AdaptiveSamplingPercentageEvaluatedCallback is another public object that changed namespaces

Fix Issue #727 .
Continuation of the same issue. found one more public object that was changed.

• I ran Unit Tests locally.

For significant contributions please make sure you have completed the following items:

• Design discussion issue #
• Changes in public surface reviewed
• CHANGELOG.md updated with one line description of the fix, and a link to the original issue.
• The PR will trigger build, unit test, and functional tests automatically. If your PR was submitted from fork - mention one of committers to initiate the build for you.

[xt0rted]

Are CI builds published to a myget feed at all? The one at https://www.myget.org/F/applicationinsights/api/v3/index.json doesn't seem to have any for the 2.6.x versions and it'd make verifying these changes easier.

[TimothyMothra]

@xt0rted I intend to publish THIS to MyGet today.

We don't auto-publish anything to MyGet as of today. Even though that's a private feed MyGet is external to our company so those packages have to be signed by Microsoft for release, and that process has specific requirements.