fix(49537): remove position relative from echarts tooltip container (#49964) (#50124)

* attempt to fix 49537 by removing position relative from the tooltip
container

* Make echart tooltip container cover all iframe area

* Update the E2E test

* Update loki snapshots from CI

* Re-enable echarts tooltip assertion.

I couldn't find a better way to fail these assertions on the previous
version of the code, but these assertions are better than nothing.

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Co-authored-by: Nicolò Pretto <info@npretto.com>
Co-authored-by: Mahatthana (Kelvin) Nomsawadi <me@bboykelvin.dev>