Improve guidance on creating corrective actions

Why is this change being made?

In !124637 (comment 1392988086) the time bounded nature of corrective actions was discussed as non-blocking item. This MR picks up that conversation into a further iteration.

Some corrective actions that are created can take a very long time to implement and fall well outside of the Corrective Action SLO. When this occurs it's often because the corrective action is not initially written in a way that focuses on resolving the issue in expedient manor. This MR is to encourage folks to write time bound corrective actions.

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