Update Docker to 20.10 in our pipelines on CI/CD

What does this MR do?

Updates Docker from 19.03.0 to 20.10.2 in our pipelines on CI/CD.

Note: only docker daemon is upgraded from 19.03.0 to 20.10.2 while docker client version is unchanged.

Related issues

Part of gitlab-org&5121 (closed)

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion

Required

• Merge Request Title, and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Integration tests added to GitLab QA
• The impact any change in container size has should be evaluated

Closes gitlab-org/charts/gitlab#2597 (closed)