[Cudo] privte networks and API/fetch fix

[JungleCatSW]

Added a private network so clusters can use it.
Also fixes the cudo fetcher
Our API has changed so also fixed API issues

Tested (run the relevant ones):

• [x ] 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: conda deactivate; bash -i tests/backward_compatibility_tests.sh

[Michaelvll]

Thanks for fixing this @JungleCatSW! I am trying this PR on my Cudo account, and we get the following error:

> sky launch --cloud cudo echo hi
HTTP response headers: HTTPHeaderDict({'Date': 'Thu, 22 Aug 2024 18:52:00 GMT', 'Content-Type': 'application/json', 'Content-Length': '342', 'Connection': 'keep-alive', 'vary': 'Origin', 'CF-Cache-Status': 'DYNAMIC', 'Report-To': '{"endpoints":[{"url":"https:\\/\\/a.nel.cloudflare.com\\/report\\/v4?s=i3xfRCICUlOVn2UKCtrEGE2CXxej%2FgWhkQsfPlqrbzOkmR7cP9KXgRHRwcu5Es6Bqp00e4uDnfjIp9QK7ggwfTNYK8KDAH2tfz%2Fr3vEXClz%2FVOR%2FQNhN5VyOIUMSy%2Bbqlhv4B%2FgyFQ%3D%3D"}],"group":"cf-nel","max_age":604800}', 'NEL': '{"success_fraction":0,"report_to":"cf-nel","max_age":604800}', 'Strict-Transport-Security': 'max-age=15552000; includeSubDomains; preload', 'X-Content-Type-Options': 'nosniff', 'Server': 'cloudflare', 'CF-RAY': '8b750eb2aa8e61d1-ORD', 'alt-svc': 'h3=":443"; ma=86400'})
E 08-22 18:52:00 provisioner.py:80] HTTP response body: {"code":9,"message":"network cannot be assigned ip from public network","details":[{"@type":"type.googleapis.com/google.rpc.PreconditionFailure","violations":[{"type":"","subject":"","description":"Public network full"}]},{"@type":"type.googleapis.com/google.rpc.ErrorInfo","reason":"NETWORK_FULL","domain":"compute.cudo.org","metadata":{}}]}

[Michaelvll]

Suggested change

	tags: Dict[str, str], disk_size: int, net_name):
	tags: Dict[str, str], disk_size: int, net_name: str) -> str: