Support GET requests in Base Client request_class

[ishields]

Simple PR to allow sending GET requests since some API calls require it. For example, this allows api calls like GET Collections to work:

@client.request_and_verify_response(:get, "/v1/api/collections")

Issue was written up here:
#117

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Note

Low Risk
Low risk: adds :get support in request dispatch with minimal surface area change and no changes to auth, response handling, or payload serialization.

Overview
Adds support for HTTP GET requests in BaseClient#request_class, allowing callers to use request/request_and_verify_response with :get instead of raising InvalidRequest.

^{Written by Cursor Bugbot for commit 4b54adf. Configure here.}

[Copilot]

Pull request overview

This PR adds support for GET HTTP requests to the BaseClient.request_class method, enabling API calls that require GET requests such as retrieving collections.

Key changes:

• Added :get case to the request_class method to support GET requests

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[Copilot]

The GET request support lacks test coverage. Consider adding a test case in spec/base_client_spec.rb similar to the existing tests for PUT requests, to verify that GET requests work correctly with both authentication methods (site_id/api_key and app_key).

[ishields]

@jcpsimmons any chance we can get this merged?