navEntry.type.replace errors with type undefined

[AndersDJohnson]

We are seeing some errors that appear to come from various browsers, e.g., Chrome 108 on Windows 10, where that navEntry.type isn't defined, such that calling .replace(...) on it is erroring out (

web-vitals/src/lib/initMetric.ts

Line 37 in 39f1782

navEntry.type.replace(/_/g, '-') as Metric['navigationType'];

).

Not sure why, as the type property there claims to be supported in that browser: https://developer.mozilla.org/en-US/docs/Web/API/PerformanceNavigationTiming/type#browser_compatibility

Perhaps these are bots that are spoofing user agent and not running in a fully compatible DOM environment.

A fix might look something like this: #290