Refactor v3 for alpha

[jaredpalmer]

• Renames unstable_StrictField to FastField.
• Deprecates <FastField shouldUpdate> prop with warning. If you need this functionality, use useFormikContext() and useField() in a custom component wrapped in React.memo() instead.
• Breaking: FastField is no longer passed a form object in any render prop. If you still need to access the form object in the render prop use Field (which updates on every render).

[changeset-bot]

🦋 Changeset detected

Latest commit: fc8be9a

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

This PR includes changesets to release 2 packages

Name	Type
formik	Patch
formik-native	Patch

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[github-actions]

Size Change: -1.31 kB (2%)

Total Size: 43.8 kB

Filename	Size	Change
packages/formik/dist/formik.cjs.development.js	17.6 kB	-449 B (2%)
packages/formik/dist/formik.cjs.production.min.js	7.67 kB	-404 B (5%)	✅
packages/formik/dist/formik.esm.js	17.4 kB	-459 B (2%)

ℹ️ View Unchanged

Filename	Size	Change
packages/formik-native/dist/formik-native.cjs.development.js	306 B	0 B
packages/formik-native/dist/formik-native.cjs.production.min.js	242 B	0 B
packages/formik-native/dist/formik-native.esm.js	238 B	0 B
packages/formik-native/dist/index.js	150 B	0 B
packages/formik/dist/index.js	143 B	0 B

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[jaredpalmer]

I am going to merge so that we can cut a release with these changes. More work needed to update tests