getMetricsForFamily returns null for font families containing multiple spaces (e.g., "IBM Plex Mono")

[AleksandrHovhannisyan]

🐛 The bug

I'm trying to read the font metrics for IBM Plex Mono (this issue is actually reproducible with any typeface that has more than one space in its family name), but getMetricsForFamily is returning null. This is because of the following line of code:

https://github.com/danielroe/fontaine/blob/e7391ee7593f4e67dbdcb8fdfd045c5fcc3f9e62/src/metrics.ts#L15

Which should do a global replacement for spaces:

const name = camelCase(family).replace(/ /g, '')

🛠️ To reproduce

N/A (invoke getMetricsForFamily with IBM Plex Mono or any other font family with multiple spaces in its name)

🌈 Expected behaviour

Current behavior: IBM Plex Mono becomes iBMPlex Mono

Expected behavior: IBM Plex Mono becomes iBMPlexMono, allowing us to key in here correctly:

https://github.com/seek-oss/capsize/blob/42d6dc39d58247bc6b9e013a4b1c4463bf287dca/packages/metrics/src/entireMetricsCollection.json#L5842-L5852

ℹ️ Additional context

No response