By Tzvi Machlin The NFL Scouting Combine is just around the corner, but participants will have to make a lot of adjustments in order to attend. On Sunday, NFL insider Tom Pelissero shared a letter sent to all draft prospects about rules for attending the Combine. With COVID-19 infection still a risk, the Combine is going to be conducted in a secured “bubble.” Leaving the bubble once invitees enter it is a non-starter. Anyone who does will be disqualified from further Combine participation and sent home. “Players will be restricted to secure Combine venues during their entire time in Indianapol…