Add support for Chromium Edge in configuration files

[spmonahan]

The docs state that performance traces are supported for Chromium-based browsers of which Edge is now one. However, I cannot enable tracing in a configuration file targeting Edge as I get a warning (this is in VSCode btw):

Property trace is not allowed

If I ignore the helpful yellow squiggly from my screenshot and try to run Tachometer with the config file I get this error

Error: config.benchmarks[0].browser is not any of <#/definitions/ChromeConfig>,<#/definitions/FirefoxConfig>,<#/definitions/SafariConfig>,<#/definitions/EdgeConfig>,<#/definitions/IEConfig>,[subschema 5]

Which is the correct behavior based on the source. While this makes sense for Edge Legacy that browser has been unsupported since March 9th, 2021 and has been replaced with Chromium Edge. This isn't an ask to drop support for Edge Legacy, at least not without a major version bump, but rather that Tachometer enable support for all the nice features Chrome enjoys in Chromium Edge as well.

Ideally Tachometer would continue to just use the name "edge" for the Edge browser and infer which schema to apply based on supplied options in the config file. If that's not possible perhaps a new browser name like "msedge"?

Happy to submit a PR too!

[aomarks]

If those options work for modern edge, I'm happy to make them supported. If they make old versions of edge crash, users can just not include the options. The errors we're talking about here are just for validation.

Would happily accept a PR.