Cherry-pick to 7.x: [CI] Enable build stage for arm architecture (#21284)#21839

Merged

v1v merged 1 commit intoelastic:7.xfrom v1v:backport/7.x/pr-21284

Oct 16, 2020

+182-9

Commits on Oct 15, 2020

[CI] Enable build stage for arm architecture (elastic#21284 )
v1v
committed