Cherry-pick to 7.x: Add 7.7.1 relnotes (#21937)#21938

Merged

dedemorton merged 1 commit intoelastic:7.xfrom dedemorton:backport/7.x/pr-21937

Oct 16, 2020

+39-1

Commits on Oct 16, 2020

Add 7.7.1 relnotes to 7.8 docs (elastic#21937 )

dedemorton
and
gbanasiak
committed