validation: add process_user validation

Signed-off-by: Zhou Hao <zhouhao@cn.fujitsu.com>

Author: Zhou Hao

validation/process_user.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"github.com/opencontainers/runtime-tools/validation/util"
+)
+
+func main() {
+	g := util.GetDefaultGenerator()
+	g.SetProcessUID(10)
+	g.SetProcessGID(10)
+	g.AddProcessAdditionalGid(5)
+
+	err := util.RuntimeInsideValidate(g, nil)
+	if err != nil {
+		util.Fatal(err)
+	}
+}