fix: use deterministic command to determine last boot time

internal/operator/nodeagent/ensure.go

@@ -1,6 +1,7 @@
 package nodeagent
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -70,14 +71,12 @@ func prepareQuery(
 
 		defer persistReadyness(curr.NodeIsReady)
 
-		dateTime, err := exec.Command("uptime", "-s").CombinedOutput()
+		dateTime, err := exec.Command("last", "reboot", "-F", "-n", "1").CombinedOutput()
 		if err != nil {
 			return noop, err
 		}
 
-		//dateTime := strings.Fields(string(who))[2:]
-		//str := strings.Join(dateTime, " ") + ":00"
-		t, err := time.Parse("2006-01-02 15:04:05", strings.TrimSuffix(string(dateTime), "\n"))
+		t, err := time.Parse(time.ANSIC, strings.Join(strings.Fields(string(bytes.Split(dateTime, []byte("\n"))[0]))[4:9], " "))
 		if err != nil {
 			return noop, err
 		}