Update gradle dependencies to 6.5#9

Merged

robbavey merged 3 commits intologstash-plugins:masterfrom

robbavey:gradle_65

Oct 26, 2020

Commits on Oct 20, 2020

Update gradle dependencies to 6.5
robbavey
committed

Commits on Oct 21, 2020

Improve gradle 6.x compatibility
robbavey
committed

Commits on Oct 26, 2020

Update version and changelog
robbavey
committed