Flaky test: Negotiate Functional Tests longPolling transport negotiate passes query string variables for persistent connections

[halter73]

  ‌HeadlessChrome 0.0.0 (Windows 10 0.0.0): Executed 164 of 168 (skipped 4)‌ SUCCESS‌ (56.813 secs / 56.649 secs)‌
  Firefox 64.0.0 (Windows 10 0.0.0): Executed 1 of 168‌ SUCCESS‌ (0 secs / 0.649 secs)‌
  ‌Firefox 64.0.0 (Windows 10 0.0.0) Core - Negotiate Functional Tests longPolling transport negotiate passes query string variables for persistent connections. (Functional) FAILED‌
    Failed to initiate signalr connection: {}
    Expected: true
    Actual: false
    wrapConnectionStart/connection.start/<@wwwroot/js/test.utilities.js:17:21
    fire@wwwroot/lib/jquery/jquery.js:3268:11
    fireWith@wwwroot/lib/jquery/jquery.js:3398:7
    Deferred/</deferred[tuple[0]]@wwwroot/lib/jquery/jquery.js:3736:36
    initialize@wwwroot/lib/signalr/jquery.signalR.js:596:21
    onFallback@wwwroot/lib/signalr/jquery.signalR.js:610:25
    transportFailed@wwwroot/lib/signalr/jquery.signalR.js:1237:17
    start/that.transportTimeoutHandle<@wwwroot/lib/signalr/jquery.signalR.js:1188:21

https://dev.azure.com/dnceng/public/_build/results?buildId=138411

[analogrelay]

Meh.