Signal that the check on line 27 shouldn't be modified

[NoisomePossum]

What does this PR do?

Adds a comment to signal to users that they shouldn't modify the code on line 27.

Motivation

Previously in our documentation we told users to add their API key in place of <DATADOG_API_KEY>. However, this string also appears in the check on line 27 and some users were modifying this as well causing the function not to complete properly. This comment will hopefully keep people from changing this line.

Testing Guidelines

Additional Notes

Types of changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• This PR impacts documentation, and it has been updated (or a ticket has been logged)
• This PR's changes are covered by the automated tests
• This PR collects user input/sensitive content into Datadog
• This PR passes the integration tests (ask a Datadog member to run the tests)
• This PR passes the unit tests