DevOps Azure will not support macOS 10.14 as of December 10

[Joshua Root]

On 2021-11-25 12:31 , Vadim-Valdis Yudaev wrote:
> Hi here,
> 
> Since that DevOps Azure will not support macOS 10.14 as of December 10, it's
> worth considering bump the version to 10.15. Otherwise, we may get a broken
> check again for PRs.
> 
>> The macOS-10.14 environment is deprecated and will be removed on December 10,
>> 2021. For more details see
>> https://devblogs.microsoft.com/devops/hosted-pipelines-image-deprecation/

We already have GitHub Actions for 10.15, so we might as well just drop 
Azure as of that date.

- Josh