Add IMOC to development director, manager, and staff engineer responsibilities

Why is this change being made?

We are expanding IMOC to development !87958 (merged) due to an action item from the .com stability daily standup.

This MR amends the duties to eligible IMOC candidates from the development department - directors, managers, and staff engineers.

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
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• Assign reviewers for this change to the correct DRI(s)
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• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR.
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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