Add configuration for custom search fields

[timleslie]

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🦋 Changeset detected

Latest commit: 7131347

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

This PR includes changesets to release 14 packages

Name	Type
@keystonejs/adapter-knex	Minor
@keystonejs/adapter-mongoose	Minor
@keystonejs/adapter-prisma	Minor
@keystone-next/website	Minor
@keystone-next/keystone	Minor
@keystone-next/types	Minor
@keystonejs/api-tests	Minor
@keystonejs/test-utils	Patch
@keystone-next/auth	Major
@keystone-next/example-auth	Patch
@keystone-next/app-basic	Patch
@keystone-next/example-ecommerce	Patch
@keystone-next/example-roles	Patch
@keystone-next/example-todo	Patch

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[gautamsi]

I like this, there is one improvement I can think of a db config searchTemplate which can take a form of function or string literal which returns the query fragment based on search input. This way the search is very useful.

My customer wanted to search from make and model field from list, also the title of ecommerce items.
@JedWatson