Repo upgrade to node 14

[tylerbutler]

Hi everyone, next week I am planning to upgrade the node version used in the repo to 14 (issue #8146). Npm will not be upgraded. The npm lockfile format will not change.

Node 14 has been used by several contributors over the past few months without issue, and I don't expect this to be a hugely disruptive change.

You can review the change in this PR: #8360. I intend to merge it on December 15.

If you want to test the changes in the PR locally, I recommend using the GitHub CLI:

gh pr checkout 8360

Then install node 14 and run npm install.

[tylerbutler]

@ruiterr @karlbom @nedalhy @evaliyev Please let me know if you have any concerns about this.

[tylerbutler]

The PR was merged!