don't leak a context in the test
diff --git a/tests/hazmat/backends/test_openssl.py b/tests/hazmat/backends/test_openssl.py
index 7125059..a212df4 100644
--- a/tests/hazmat/backends/test_openssl.py
+++ b/tests/hazmat/backends/test_openssl.py
@@ -98,7 +98,9 @@
 
     def test_ssl_ciphers_registered(self):
         meth = backend._lib.TLSv1_method()
-        assert backend._lib.SSL_CTX_new(meth) != backend._ffi.NULL
+        ctx = backend._lib.SSL_CTX_new(meth)
+        assert ctx != backend._ffi.NULL
+        backend._lib.SSL_CTX_free(ctx)
 
     def test_evp_ciphers_registered(self):
         cipher = backend._lib.EVP_get_cipherbyname("aes-256-cbc")