Drop the never-ran reading: a start timestamp of 0 does not mean a one-shot never ran (issue 1126)

Review round 1 measured it on systemd 262.1: a finished one-shot nothing references is
unloaded, and loaded again it reads inactive, ExecMainStatus=0 and a start timestamp of
0, as one that never ran does. The previous commit's rule read such a unit stopped, so
a one-shot declared running would be started, read stopped and fail on every apply, and
the hold, the take-over and the giving back would judge it wrongly.

ServiceState keeps main's reading. ServiceAtRest and declaredState stay: they alone
satisfy a stopped declaration for a one-shot at rest, which is the kernel cleanup's
case. A one-shot declared running that must be seen to have run lingers
(RemainAfterExit) or is enabled at boot. Unit tests: the arch table has 5 rows, the
apply test 1; 1262 in all.

internal/apply/apply_test.go

@@ -351,14 +351,12 @@ func TestAnUnknownServiceStateIsRefusedNotGuessed(t *testing.T) {
 }
 
 // A boot-time one-shot a package ships, declared stopped and enabled at boot, is satisfied while
-// nothing of it runs: before its first boot run and after it (novox/hq issue 1126). The kernel
-// module's linux-modules-cleanup.service failed on ace with "was asked to be stopped and is
-// running" for a unit that had never run, and every apply after a reboot would have failed the
-// same way for one that had.
+// nothing of it runs, whatever its last run did (novox/hq issue 1126). The kernel module's
+// linux-modules-cleanup.service failed on ace with "was asked to be stopped and is running": an
+// inactive one-shot with ExecMainStatus=0 reads "running", and stopping it changes nothing.
 func TestABootOneShotDeclaredStoppedIsSatisfiedAtRest(t *testing.T) {
-	for _, c := range []struct{ name, started, status string }{
-		{"never ran", "0", "0"},
-		{"ran at boot", "5123456", "0"},
+	for _, c := range []struct{ name, status string }{
+		{"exited 0: never ran, ran at boot, or unloaded", "0"},
 	} {
 		t.Run(c.name, func(t *testing.T) {
 			var asked []string
@@ -367,7 +365,7 @@ func TestABootOneShotDeclaredStoppedIsSatisfiedAtRest(t *testing.T) {
 				switch args[0] {
 				case "show":
 					return "LoadState=loaded\nActiveState=inactive\nType=oneshot\nRemainAfterExit=no\n" +
-						"ExecMainStatus=" + c.status + "\nExecMainStartTimestampMonotonic=" + c.started + "\n", nil
+						"ExecMainStatus=" + c.status + "\n", nil
 				case "is-enabled":
 					return "enabled\n", nil
 				}