Fix failing tests 3

Author: SOHELAHMED7

tests/spec/OpenApiTest.php

@@ -222,7 +222,7 @@ public function testSpecs($openApiFile)
 
         // security
         $openapi->security !== null && $this->assertInstanceOf(\cebe\openapi\spec\SecurityRequirements::class, $openapi->security);
-        $this->assertAllInstanceOf(\cebe\openapi\spec\SecurityRequirement::class, $openapi->security->getRequirements());
+        $openapi->security !== null && $this->assertAllInstanceOf(\cebe\openapi\spec\SecurityRequirement::class, $openapi->security->getRequirements());
 
         // tags
         $this->assertAllInstanceOf(\cebe\openapi\spec\Tag::class, $openapi->tags);