feat: turn on DD profiling timeline.

[dianakhuang]

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Make sure that the following steps are done before merging:

• Have a Site Reliability Engineer review the PR if you don't own all of the services impacted.
• If you are adding any new default values that need to be overridden when this change goes live, update internal repos and add an entry to the top of the CHANGELOG.
• Performed the appropriate testing.

[timmc-edx]

May want to add a comment indicating that this is temporary and in pursuit of debugging, rather than a feature we specifically wanted.

[dianakhuang]

I don't know. I think it's possible it will be useful in the future if it does help with debugging.