Fix unnecessary rendering of FastField

[mvestergaard]

Whenever Context changes, shouldComponentUpdate is not called, which caused FastField to always re-render whenever Context changes
This adds a wrapper around FastField that grabs the Context, and passes it down as props

Fixes #1974, #2042, #1759

May depend on #2069 to be entirely fixed

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Sandbox	Source
Formik TypeScript Playground	Configuration
billowing-violet-psjez	Issue #1974
frosty-booth-v9r4r	Issue #1974

[mvestergaard]

I tried my best to write a test that reproduces the problem, but it's really difficult, if not impossible in a "fake context".
Use the FastField story in the formik storybook to compare the behavior to before.

[mvestergaard]

@jaredpalmer Can you take another look at this please? And possibly publish a new release including this and #2069
Large forms are presently close to unusable

[jaredpalmer]

Publishing meow

[mhaylock]

@jaredpalmer what is the status of that release?

I went to look for the release attached to your comment above but I see the last release was 2.0.6, 17 days ago.