Documenting policy regarding account reclaim during offboarding

Why is this change being made?

I am adding this information into the handbook as it used to previously live on the IT Ops handbook page but got merged out without anyone realizing. It is currently documented in the offboarding template here under the IT Operations section but should also be documented on a controlled handbook page.

This is a policy that we have been following for 2 years now and is not new.

@disla Can you please review my wording on this and make any tweaks you deem necessary? Once reviewed, please comment your approval and we can mark as ready to have Julia merge.

FYI @gl-people-connect-team

Author Checklist

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