feat: provide current values as context to yup validation by default

[quantizor]

Yup by default only allows for cross-field validation within the same field object. This is not that useful in most scenarios because a sufficiently-complex form will have several yup.object() in the schema.

const deepNestedSchema = Yup.object({
  object: Yup.object({
    nestedField: Yup.number().required(),
  }),
  object2: Yup.object({
    // this doesn't work because `object.nestedField` is outside of `object2`
    nestedFieldWithRef: Yup.number().min(0).max(Yup.ref('object.nestedField')),
  }),
});

However, Yup offers something called context which can operate across the entire schema when using a $ prefix:

const deepNestedSchema = Yup.object({
  object: Yup.object({
    nestedField: Yup.number().required(),
  }),
  object2: Yup.object({
    // this works because of the "context" feature, enabled by $ prefix
    nestedFieldWithRef: Yup.number().min(0).max(Yup.ref('$object.nestedField')),
  }),
});

With this change, you may now validate against any field in the entire schema, regardless of position, when using the $ prefix.

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Name	Status	Preview	Comments	Updated (UTC)
formik-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	May 26, 2023 6:10pm

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[jaredpalmer]

I'm gonna merge the others and release and then merge this and then release a minor