doc: release notes for 7.1.2
doc: release notes for 7.1.2

sharang108/checkstyle,checkstyle/checkstyle,bansalayush/checkstyle,jochenvdv/checkstyle,checkstyle/checkstyle,MEZk/checkstyle,jonmbake/checkstyle,sabaka/checkstyle,jochenvdv/checkstyle,rnveach/checkstyle,jonmbake/checkstyle,bansalayush/checkstyle,romani/checkstyle,checkstyle/checkstyle,sharang108/checkstyle,MEZk/checkstyle,MEZk/checkstyle,sabaka/checkstyle,checkstyle/checkstyle,sabaka/checkstyle,sirdis/checkstyle,nikhilgupta23/checkstyle,sharang108/checkstyle,romani/checkstyle,rnveach/checkstyle,rnveach/checkstyle,vboerchers/checkstyle,AkshitaKukreja30/checkstyle,romani/checkstyle,izishared/checkstyle,rnveach/checkstyle,checkstyle/checkstyle,izishared/checkstyle,izishared/checkstyle,vboerchers/checkstyle,romani/checkstyle,liscju/checkstyle,bansalayush/checkstyle,liscju/checkstyle,nikhilgupta23/checkstyle,romani/checkstyle,nikhilgupta23/checkstyle,AkshitaKukreja30/checkstyle,romani/checkstyle,jonmbake/checkstyle,sirdis/checkstyle,rnveach/checkstyle,sirdis/checkstyle,ilanKeshet/checkstyle,ilanKeshet/checkstyle,checkstyle/checkstyle,rnveach/checkstyle,vboerchers/checkstyle,jochenvdv/checkstyle,AkshitaKukreja30/checkstyle,ilanKeshet/checkstyle,liscju/checkstyle