[master] Remove Linode API v3 usage

[zliang-akamai]

What does this PR do?

This PR removes the usage of retired Linode API v3 from salt cloud.

What issues does this PR fix or reference?

Fixes: #64517

Previous Behavior

User can use both Linode API v3 and v4.

New Behavior

User can only use Linode API v4.

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

Yes

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[zliang-akamai]

The integration test run reporting an error but I don't think it is related to this Linode salt cloud module change. Any suggestion?

Update:
Just tested it again against the salt cloud before the change proposed in this PR, and it looks like that the errors were there already.

tests/integration/cloud/clouds/test_linode.py::LinodeTest::test_instance [WARNING ] There's no master defined on the 'cloud-test-lin-4zps7v' VM settings.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
No ED25519 host key is known for 23.239.13.93 and you have requested strict checking.
Host key verification failed.
[ERROR   ] Failed to start Salt on host cloud-test-lin-4zps7v

[zliang-akamai]

Hi @cmcmarrow, is there anything still needed from us to get this PR reviewed?

[cmcmarrow]

Hi @zliang-akamai thanks for waiting. Your code changes look good, once the tests get done running and are green I'll approve.

[Ch3LL]

This looks good. We're just waiting for a merge forward PR for those package tests to start passing. I'll update the branch once that's merged in.

[welcome]

Congratulations on your first PR being merged! 🎉