Missing support for platform param in images.build

[AndreaCensi]

The most recent versions of Docker support a platform parameter:

https://docs.docker.com/engine/api/v1.41/#operation/ImageBuild

(This can be used, for example, to build amd64 images on an arm64 machine.)

Currently this parameter is not passed:

aiodocker/aiodocker/images.py

Lines 310 to 319 in 26f4361

	params = {
	"t": tag,
	"rm": rm,
	"q": quiet,
	"pull": pull,
	"remote": remote,
	"nocache": nocache,
	"forcerm": forcerm,
	"dockerfile": path_dockerfile,
	}

[asvetlov]

Pull request is welcome!
At least a simple test is required.