Fixes compilation break on Windows

This doesn't fix all the tests or make binaries avaiable. It just makes
it possible to compile on windows.

Author: Adrian Cole

internal/envoy/procattr.go internal/envoy/procattr_darwin.go

@@ -12,8 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build !linux
-
 package envoy
 
 import (

internal/envoy/procattr_windows.go

@@ -0,0 +1,25 @@
+// Copyright 2021 Tetrate
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package envoy
+
+import (
+	"syscall"
+)
+
+func sysProcAttr() *syscall.SysProcAttr {
+	// TODO: We don't use syscall.CREATE_NEW_PROCESS_GROUP because we want external killing of getenvoy to kill the
+	// spawned process. If we put this in a new process group, that wouldn't happen. Either way this is as yet untested.
+	return &syscall.SysProcAttr{}
+}