* ci: add macos-11.0
* ci: update runners
* Restore ubuntu-18.04 back
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Signed-off-by: Tao He <sighingnow@gmail.com>
Co-authored-by: Tao He <sighingnow@gmail.com>
* Enable keys() to list elements without fetching values from server
* Add concurrency control and cancel to CI workflows
Signed-off-by: Tao He <sighingnow@gmail.com>