Clear some sslapitest global variables after use
Otherwise we get a use after free if the test order is randomised.
@@ -3227,6 +3227,7 @@ static int test_export_key_mat_early(int idx)
SSL_SESSION_free(sess);
SSL_SESSION_free(clientpsk);
SSL_SESSION_free(serverpsk);
+ clientpsk = serverpsk = NULL;
SSL_free(serverssl);
SSL_free(clientssl);
SSL_CTX_free(sctx);
