Update Handbook for NL Sick leave

Why is this change being made?

To provide more clarity to the timeline of long term sick leave and reporting to HR Savvy.

@jkalimon I wonder if the reporting ideally should go via People Ops (as is?) and if they have bandwidth? Or via another team?

@glucchesi @emilyplotkin @tnix Aligning 1 work week to reflect 8 days (as with the general guideline). 8 days should be sufficient to distinct short term (ex. flu) from long term illness (ex. severe health issues). Also this would align with the requirement to have a Plan of Action in place by the 6th week of absence. Please review and let me know your thoughts!

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
• Assign this change to the correct DRI
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