update a call to the package:shelf_web_socket webSocketHandler() function

[devoncarew]

• update a call to the package:shelf_web_socket webSocketHandler() function

This code site returns a diagnostic when used with package:shelf_web_socket v3, and we need to roll both that version and this code into google3.

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[devoncarew]

I don't know that the windows failures are related to this PR; I see bot failures for other recent PRs.

[nshahan]

I don't know that the windows failures are related to this PR; I see bot failures for other recent PRs.

I agree, we have been investigating these flakes already.