Add warning for python 2.7 on release/v2 (actions#675)

* add warning

* remove ubuntu-18.04

* remove macos-10.15

* fix pypy3

Add warning for python 2.7 (actions#673)

update @azure/storage-blob (actions#655)

Update actions/core for releases/v3 (actions#624)

update actions/core (actions#625)

update actions/core (actions#625)

Fix outdated ref to actions/setup-python@v3 in doc (actions#581)

Install multiple python versions (actions#567)

Add OS info to the error message (actions#559)

Update actions/core to 1.10.0 for v2 (actions#533)