Add the //go:build tags

Author: fsouza

integration_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build docker_integration
 // +build docker_integration
 
 package docker

integration_unix_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build docker_integration && !windows
 // +build docker_integration,!windows
 
 package docker

integration_windows_test.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build docker_integration
 // +build docker_integration
 
 package docker