[feat] Add support for premium_40GB NodeBalancer type

[komer3]

LinodeGo PR that supports this feature: linode/linodego#867

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Pull Request Guidelines:

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[codecov]

Codecov Report

❌ Patch coverage is 60.00000% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.62%. Comparing base (ab91991) to head (89b82d1).

Files with missing lines	Patch %	Lines
cloud/linode/loadbalancers.go	50.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #507      +/-   ##
==========================================
- Coverage   73.72%   73.62%   -0.10%     
==========================================
  Files          19       19              
  Lines        2835     2840       +5     
==========================================
+ Hits         2090     2091       +1     
- Misses        504      508       +4     
  Partials      241      241              

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[AshleyDumaine]

Do we want to warn when the annotation is an invalid type instead of just silently defaulting to the default NBType?

[komer3]

Hmm, we could warn and then just default to basic NB?