Fix dead links in Server Hardware Requirements Guide page

Dear Documentation Team,

On the page Server Hardware Requirements Guide under Professional assistance, the 2 links are broken and leads to 404 page:

Specifically the link for "Atlassian Expert" and "contact a local Expert directly"

For large instances, it may be worthwhile contacting an Atlassian Expert for expertise on hardware sizing, testing and performance tuning. Simply contact a local Expert directly or email our Experts team for a recommendation.