Update Australia's Parental Leave reporting instructions and payment scheme

Why is this change being made?

Australia requires team members to provide written notice of their request for Parental leave within a very specific timeline that was not previously included in these instructions. Employers were also asked to provide a Parental leave checklist to team members to help ensure that all timelines are met. This checklist is now added and instructions to team members on how to provide their written requests are also included.

The Parental leave income eligibility requirements for Paid Parental leave in Australia changed from the 2019/2020 financial year to 2020/2021 financial year, but that change was not reflected in this MR. I anticipate these amounts could change again in the future so rather than including a specific amount, I've provided the website to these benefits so team members can review them on their own.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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