Remove old AWS node provider

[suquark]

With the new provisioner shipped for a while and no significant issues, now we can consider deprecating the old AWS node provider. In theory this should not break any tests. I still need to run smoke tests to confirm it though.

Tested (run the relevant ones):

• Code formatting: bash format.sh
• Any manual or new tests for this PR (please specify below)
• All smoke tests: pytest tests/test_smoke.py
• Relevant individual smoke tests: pytest tests/test_smoke.py::test_fill_in_the_name
• Backward compatibility tests: bash tests/backward_comaptibility_tests.sh

[suquark]

@Michaelvll I tried to test this PR but find may smoke tests failed due to insufficient quotas. Could you test it for me? I think running smoke tests should be good enough, since these code should not interfere with our current functionality. Thanks!

[Michaelvll]

Thaanks for submitting this PR @suquark! I am testing the following tests:

• pytest tests/test_smoke.py
• bash -i ./tests/backward_compatibility_tests.sh
• pytest tests/test_smoke.py --aws

[Michaelvll]

Thanks for removing the staled node_providers for AWS @suquark! It seems working nicely and passed all the smoke tests. It should be good to go in. : )