Encode VAPID key in URL-safe base64 (#220)

*  fix base64encode issue

*  typo ~ fix Base64Url::encode

*  fix phpunit testing

*  fix The condition becomes ">=86" and ">=42"

Author: vockalimo

src/VAPID.php

@@ -190,8 +190,8 @@ public static function createVapidKeys(): array
         }
 
         return [
-            'publicKey' => base64_encode($binaryPublicKey),
-            'privateKey' => base64_encode($binaryPrivateKey)
+            'publicKey'  => Base64Url::encode($binaryPublicKey),
+            'privateKey' => Base64Url::encode($binaryPrivateKey)
         ];
     }
 }

tests/VAPIDTest.php

@@ -98,7 +98,7 @@ public function testCreateVapidKeys()
         $keys = VAPID::createVapidKeys();
         $this->assertArrayHasKey('publicKey', $keys);
         $this->assertArrayHasKey('privateKey', $keys);
-        $this->assertEquals(strlen($keys['publicKey']), 88);
-        $this->assertEquals(strlen($keys['privateKey']), 44);
+        $this->assertGreaterThanOrEqual(86, strlen($keys['publicKey']));
+        $this->assertGreaterThanOrEqual(42, strlen($keys['privateKey']));
     }
 }