chore: bump suggested local dev node version

[trentm]

Change #2831 showed an example where node v16.15.0 and ealier were
insufficient for our dist build. The dist build for release is done by
CI that specifies the requisite node version, but it could be helpful
for a local dev to have a sufficient version.

.nvmrc is just advisory, so there is no expected impact.

[ghost]

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• Start Time: 2022-08-02T23:34:44.777+0000

• Duration: 19 min 50 sec

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Total	257814

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