Updating PTO details under ABCs of Employment Law

Why is this change being made?

The PTO details were still referencing the Don't Ask, Do Tell policy which has since been updated to a Flexible PTO policy (see !102691 (merged)). Updating and linking here. Also taking the opportunity to improve readability of the list.

Adding @tnix @emilyplotkin and @jbandur as reviewers as this section was added in !96122 (merged) and not modified since. Thanks in advance!

Author Checklist

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• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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