De-duplicate performance.mark and performance.measure

`performance.measure()` requires a start and end mark. In our marker processing step we should de-duplicate the marks that are used to create measures. Currently we are showing 3 markers for every 1 measure.

This work should most likely be done in: https://github.com/devtools-html/perf.html/blob/7d9ac63cb58629a458d96a7a9150716cdc358ee4/src/profile-logic/profile-data.js#L905-L959

┆Issue is synchronized with this [Jira Task](https://mozilla-hub.atlassian.net/browse/FP-675)