Release memory for subject alt name in test

Signed-off-by: Przemek Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/tests/suites/test_suite_x509parse.function b/tests/suites/test_suite_x509parse.function
index c7d341d..4d89410 100644
--- a/tests/suites/test_suite_x509parse.function
+++ b/tests/suites/test_suite_x509parse.function
@@ -1506,7 +1506,7 @@
     int bufferCounter = 0;
     size_t issuerCounter = 0;
     unsigned int result = 0;
-    mbedtls_x509_subject_alternative_name san = { 0 };
+    mbedtls_x509_subject_alternative_name san;
     mbedtls_x509_name *pname = NULL;
 
     mbedtls_x509_crt_init(&crt);
@@ -1533,6 +1533,7 @@
             bufferCounter++; /* Skipping the slash */
             pname = pname->next;
         }
+        mbedtls_x509_free_subject_alt_name(&san);
         TEST_ASSERT(result == 0);
 
         /* Serial test */