add empty input warning to catalystcenter_*_settings resources

[kuba-mazurkiewicz]

There is undocumented API issue that throws following error:

 Failed to delete object (PUT), got error: HTTP Request failed: StatusCode 400, {"response":{"errorCode":"NCND01090","message":"NCND01090: Empty input - the groupUuid is null or
│ empty","href":"/intent/api/v1/sites/4c06e542-8bc8-4c34-988a-b98030e46229/aaaSettings"},"version":"1.0"}

when trying to remove settings from Global level.

To bypass this I added following code block under DELETE method:

		errorCode := res.Get("response.errorCode").String()
		if errorCode == "NCND01090" {
			// Log a warning and continue execution when Empty input - the groupUuid is null or empty
			failureReason := res.Get("response.failureReason").String()
			resp.Diagnostics.AddWarning("Empty input Warning", fmt.Sprintf("Empty input detected (error code: %s, reason %s).", errorCode, failureReason))
		} else {
			resp.Diagnostics.AddError("Client Error", fmt.Sprintf("Failed to delete object (%s), got error: %s, %s", "PUT", err, res.String()))
			return
		}

[kuba-mazurkiewicz]

I also fixed pipeline with acceptance tests for settings