Make collect-info multi-arch compatible, providing arm64 support

[michaelsembwever]

The tests seem to have a bad time tho.

happens sometimes. restarted them.

[michaelsembwever]

Clean CI.

Additional adjustments to integration tests:

• Had to remove the macos step, as the macos runners are now arm64 mX based and don't support docker.
• Upgraded cass-operator, Cassandra, and DSE versions used in the tests.
• Reduced DSE tests to single node.
• Had to use --force-conflicts --server-side on cass-operator, see https://github.com/k8ssandra/k8ssandra/issues/1380
• Added iproute2 to test images (to get ip command)
• A darwin arm64 collect-info is built if the local machine is such and ructc is on the path, and this is used when running ds-collector, on the assumption this is a mac mX machine running integration tests. A clear message is printed if this assumption is wrong and how to remedy it.
• The use of df command is made macos friendly in ds-collector (for the above point).

Also added the licence header to ds-collector script.