"take not of" typo corrected to "take note of"

[JeeWeetje]

Checklist

• I have read the [contribution guidelines] (https://github.com/Azure/azure-iot-sdk-java/blob/master/.github/CONTRIBUTING.md).
• I added or modified the existing tests to cover the change (we do not allow our test coverage to go down).
• If this is a modification that impacts the behavior of a public API
  • I edited the corresponding document in the devdoc folder and added or modified requirements.
• I submitted this PR against the correct branch:
  • This pull-request is submitted against the master branch.

Reference/Link to the issue solved with this PR (if any)

Description of the problem

Fixed a small typo in the markdown file. Corrected "... take not of ..." to "... take note of ...".

Description of the solution

I added a correctly spelled e to not to change something negative to something noticeable. ;-)

[msftclas]

This seems like a small (but important) contribution, so no Contribution License Agreement is required at this point. We will now review your pull request.
Thanks,
Microsoft Pull Request Bot