integration_test: no arch for PullImage Platform
integration_test: no arch for PullImage Platform

Prevents error that seems to occur on URL:
  /v1.34/images/create?fromImage=fsouza%2Fgo-dockerclient-integration%3Awindows&platform=windows%2Famd64

--- FAIL: TestIntegrationPullCreateStartLogs (0.00s)

    integration_test.go:96: Pull output:

    integration_test.go:97: API error (500): invalid platform: invalid platform architecture "amd64"

fsouza/go-dockerclient