api: remove enum validation on ALPNProtocol

[zirain]

This will allow us to config that ALPNProtocol when trying to integrate other OSS project(e.g. Istio).

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 71.03%. Comparing base (bb3f4ba) to head (db8db9c). :warning: Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6330      +/-   ##
==========================================
+ Coverage   71.02%   71.03%   +0.01%     
==========================================
  Files         226      226              
  Lines       40037    40037              
==========================================
+ Hits        28435    28440       +5     
+ Misses       9920     9915       -5     
  Partials     1682     1682              

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[guydc]

If we don't have a validation, can we still keep a comment outlining the "typical" values http/1.0;http/1.1;h2 that most users should choose from?

[zirain]

typical

it's there:

        // ALPNProtocols supplies the list of ALPN protocols that should be
	// exposed by the listener or used by the proxy to connect to the backend.
	// Defaults:
	// 1. HTTPS Routes: h2 and http/1.1 are enabled in listener context.
	// 2. Other Routes: ALPN is disabled.
	// 3. Backends: proxy uses the appropriate ALPN options for the backend protocol.
	// When an empty list is provided, the ALPN TLS extension is disabled.
	// Typical Supported values are:
	// - http/1.0
	// - http/1.1
	// - h2
	//
	// +optional

[github-actions[bot]]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. Please feel free to give a status update now, ping for review, when it's ready. Thank you for your contributions!