Fix: PodDisruptionBudgetTest Consistent 409s

Issue here likely due to speed of test versus timing in VM.
Trying to eliminate this timing issue in this test.
Unclear if 409s should be resolved in client code with a loop or in the library.

Author: cuppett

tests/PodDisruptionBudgetTest.php

@@ -153,13 +153,21 @@ public function runGetTests()
 
     public function runUpdateTests()
     {
-        $pdb = $this->cluster->getPodDisruptionBudgetByName('mysql-pdb');
-
-        $this->assertTrue($pdb->isSynced());
-
-        $pdb->setMinAvailable('25%');
-
-        $pdb->createOrUpdate();
+        $backoff = 0;
+        do {
+            try {
+                $pdb = $this->cluster->getPodDisruptionBudgetByName('mysql-pdb')->setMinAvailable('25%')->createOrUpdate();
+            } catch (KubernetesAPIException $e) {
+                if ($e->getCode() == 409) {
+                    sleep(2*$backoff);
+                    $backoff++;
+                } else {
+                    throw $e;
+                }
+                if ($backoff > 3)
+                    break;
+            }
+        } while (!isset($pdb));
 
         $this->assertTrue($pdb->isSynced());