This diff is a small follow-up from the landed D4741 comment to remove a duplicate condition from waitUntilReady() function which is covered by the while condition.

Docker:
Run yarn run-tunnelbroker-service successfully built.

Nix:
Run nix develop, cd services/tunnelbroker, rm -dfr build && cmake -B build . && make -C build -j4. Expect successfully building the app.