Revert "[RPP Observations] Add phases for each interaction"

This reverts commit a51d9f907b439d236bb53a9b4f6e6544c4637c9f.

Reason for revert: e2e test on mac consistently fails since this CL landed. First failure: https://ci.chromium.org/ui/p/devtools-frontend/builders/ci/Stand-alone%20Mac-arm64/4134/overview.

Original change's description:
> [RPP Observations] Add phases for each interaction
>
> - Interaction list items are expandable
> - Creates separate interaction if events happen in different frames
> - Interactions are restored from the buffer
> - `eventNames` property added to each interaction for future use
>
> Bug: 369097528, 365160880, 371052022
> Change-Id: Iab39cb300143aad3a6f2cc5ef5ecab79d7fd879e
> Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5933344
> Reviewed-by: Paul Irish <paulirish@chromium.org>
> Commit-Queue: Adam Raine <asraine@chromium.org>

Bug: 369097528, 365160880, 371052022
Change-Id: I7cd208c5e2620c682f9babaec573df4c0880cfb6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5938363
Auto-Submit: Simon Zünd <szuend@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>