Fix "engines" field missing in published package

[marvinhagemeister]

• Up node requirement to 12.17.x
• Fix engines field not being included in published package.json

Fixes #236 .

[changeset-bot]

🦋 Changeset detected

Latest commit: 7b94673

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
wmr	Patch

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[github-actions]

Size Change: 0 B

Total Size: 734 kB

ℹ️ View Unchanged

Filename	Size	Change
examples/demo/dist/about/index.html	673 B	0 B
examples/demo/dist/assets/Calendar.********.css	702 B	0 B
examples/demo/dist/assets/style.********.css	624 B	0 B
examples/demo/dist/chunks/class-fields.********.js	209 B	0 B
examples/demo/dist/chunks/compat.********.js	15.3 kB	0 B
examples/demo/dist/chunks/index.********.js	303 B	0 B
examples/demo/dist/chunks/json.********.js	236 B	0 B
examples/demo/dist/chunks/prerender.********.js	2.46 kB	0 B
examples/demo/dist/class-fields/index.html	657 B	0 B
examples/demo/dist/compat/index.html	1.51 kB	0 B
examples/demo/dist/env/index.html	732 B	0 B
examples/demo/dist/error/index.html	662 B	0 B
examples/demo/dist/files/index.html	692 B	0 B
examples/demo/dist/index.********.js	7.45 kB	0 B
examples/demo/dist/index.html	721 B	0 B
examples/demo/dist/json/index.html	671 B	0 B
examples/demo/dist/lazy-and-late/index.html	674 B	0 B
packages/wmr/wmr.cjs	700 kB	0 B

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