Bump nvmrc to Node.js v18

[kassens]

Bump nvmrc to Node.js v18

Node.js v16 is long deprecated, seems like for v20 there's some more stuff to fix.

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• Upgrade to Rollup 4 #28704
• -> Bump nvmrc to Node.js v18 #28707

[kassens]

I think this might fix the build issues from #28704.

[react-sizebot]

Comparing: 6e65010...8138d81

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js	=	177.10 kB	177.10 kB	=	55.05 kB	55.05 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js	=	172.94 kB	172.94 kB	=	53.91 kB	53.91 kB
facebook-www/ReactDOM-prod.classic.js	=	592.68 kB	592.68 kB	=	103.96 kB	103.96 kB
facebook-www/ReactDOM-prod.modern.js	=	574.37 kB	574.37 kB	=	100.98 kB	100.98 kB
test_utils/ReactAllWarnings.js	Deleted	64.93 kB	0.00 kB	Deleted	16.24 kB	0.00 kB

Significant size changes

Includes any change greater than 0.2%:

Expand to show

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
test_utils/ReactAllWarnings.js	Deleted	64.93 kB	0.00 kB	Deleted	16.24 kB	0.00 kB

Generated by 🚫 dangerJS against 8138d81

[kassens]

v20 causes other failures… trying 18 for now as a smaller step upgrade.