Strict mode requires Client::sendRequest(RequestInterface $request) to return a ResponseInterface but the return type is not declared.
Specific error:
{"error":{"code":500,"message":"Internal Server Error","exception":[{"message":"Compile Error: Declaration of Smalot\\Cups\\Transport\\Client::sendRequest(Psr\\Http\\Message\\RequestInterface $request) must be compatible with Psr\\Http\\Client\\ClientInterface::sendRequest(Psr\\Http\\Message\\RequestInterface $request):
Strict mode requires Client::sendRequest(RequestInterface $request) to return a ResponseInterface but the return type is not declared.
Specific error:
{"error":{"code":500,"message":"Internal Server Error","exception":[{"message":"Compile Error: Declaration of Smalot\\Cups\\Transport\\Client::sendRequest(Psr\\Http\\Message\\RequestInterface $request) must be compatible with Psr\\Http\\Client\\ClientInterface::sendRequest(Psr\\Http\\Message\\RequestInterface $request):