When an array is specified as the default value for a query parameter, the value is incorrectly output as a serialized Java array, which leads to invalid Go client code. This adds an extra check to output default array values in the expected syntax and adds the value to the query parameters.

The existing r.{{paramName}} = &defaultValue line in the template was preserved as an existing behavior, though I'm not entirely sure what it does in this context.

Fixes #21077

@antihax @grokify @kemokemo @jirikuncar @ph4r5h4d @lwj5

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