fix: update the date for meeting

as per graphql/graphql-js#2787 (comment) meeting should be on 28th not 27th

agendas/2020-10-28.md

@@ -6,7 +6,7 @@ relevant topics to core GraphQL projects. This is an open meeting in which
 anyone in the GraphQL community may attend. *To attend this meeting or propose
 agenda, edit this file.*
 
-- **Date & Time**: [October 27th 2020 16:00 - 19:00 UTC](https://www.timeanddate.com/worldclock/meetingdetails.html?year=2020&month=10&day=27&hour=16&min=0&sec=0&p1=224&p2=179&p3=136&p4=37&p5=239&p6=101&p7=152), view the [calendar](https://calendar.google.com/calendar/embed?src=linuxfoundation.org_ik79t9uuj2p32i3r203dgv5mo8%40group.calendar.google.com), or subscribe ([Google Calendar](https://calendar.google.com/calendar?cid=bGludXhmb3VuZGF0aW9uLm9yZ19pazc5dDl1dWoycDMyaTNyMjAzZGd2NW1vOEBncm91cC5jYWxlbmRhci5nb29nbGUuY29t), [ical file](https://calendar.google.com/calendar/ical/linuxfoundation.org_ik79t9uuj2p32i3r203dgv5mo8%40group.calendar.google.com/public/basic.ics)).
+- **Date & Time**: [October 28th 2020 16:00 - 19:00 UTC](https://www.timeanddate.com/worldclock/meetingdetails.html?year=2020&month=10&day=28&hour=16&min=0&sec=0&p1=224&p2=179&p3=136&p4=37&p5=239&p6=101&p7=152), view the [calendar](https://calendar.google.com/calendar/embed?src=linuxfoundation.org_ik79t9uuj2p32i3r203dgv5mo8%40group.calendar.google.com), or subscribe ([Google Calendar](https://calendar.google.com/calendar?cid=bGludXhmb3VuZGF0aW9uLm9yZ19pazc5dDl1dWoycDMyaTNyMjAzZGd2NW1vOEBncm91cC5jYWxlbmRhci5nb29nbGUuY29t), [ical file](https://calendar.google.com/calendar/ical/linuxfoundation.org_ik79t9uuj2p32i3r203dgv5mo8%40group.calendar.google.com/public/basic.ics)).
 
   <small>*NOTE:* Meeting date and time may change. Please check this agenda the week of the meeting to confirm.</small>
 - **Video Conference Link**: https://zoom.us/j/593263740