test(e2e): make parity runners environment-safe

tools/frontend-legacy-parity/testUrls.ts

@@ -0,0 +1,7 @@
+const gatewayPort = process.env.FRONTEND_PARITY_GATEWAY_PORT ?? '15100';
+const gamePort = process.env.FRONTEND_PARITY_GAME_PORT ?? '15102';
+
+export const gatewayOrigin = `http://127.0.0.1:${gatewayPort}`;
+export const gameOrigin = `http://127.0.0.1:${gamePort}`;
+export const gatewayUrl = (suffix = '/'): string => `${gatewayOrigin}/gateway${suffix}`;
+export const gameUrl = (suffix = '/'): string => `${gameOrigin}/che${suffix}`;