Log something in the event we cannot push an experiment to Gon

This issue is a developer-focused improvement to the experiment framework (GLEX).

The way the code is currently written, if we are unable to push an experiment context to the frontend for tracking, we just silently ignore that exception in all environments and move on.

The proposed improvement is that we would actually log something somewhere in such an event so that the developer would be alerted early on – while they are still building an experiment, for example – that something is not working as they expected or intended.

---

The following discussion from !67366 (merged) should be addressed:

• @mkaeppler started a discussion: (+1 comment)

  Not strictly part of this MR, but while we're here, would it make sense to address this? This will swallow programming mistakes and could be very difficult to track down for future-us. WDYT?