fix(client): expose Client struct for provider to use

[mjunglw]

Basic requirement from Terraform-Provider-Lacework -> cast interface{} into your client

This is how we set it up on provider.go:

func providerConfigure(d *schema.ResourceData) (interface{}, error) {
	client, err := client.New(
		d.Get("account").(string),
		client.WithApiKeys(d.Get("key_id").(string), d.Get("secret").(string)),
	)
	if err != nil {
		return nil, err
	}

	return client, nil
}

Example:

func resourceLaceworkIntegrationAWSCFGCreate(d *schema.ResourceData, meta interface{}) error {
	client := meta.(*client.Client)
	client.GetIntegrations()
	return nil
}

I think exposing Client should be enough. I don't think we need to do anything extravagant:

type Client struct {
	account    string
	apiVersion string
	baseURL    *url.URL
	auth       *authConfig
	c          *http.Client
}

Thoughts? @afiunelw, @scottford-lw, @lwmobeent

[ghost]

Yes, yes and yes!!