Session cookie sameSite option

[timleslie]

This PR brings in the changes from #2602 with minor documentation tweaks. All credit goes to @ropaolle 🎉

Fixes #2551

[changeset-bot]

🦋 Changeset is good to go

Latest commit: 10eb10c

We got this.

This PR includes changesets to release 24 packages

Name	Type
@keystonejs/keystone	Major
@keystonejs/session	Major
@keystonejs/adapter-knex	Patch
@keystonejs/adapter-mongoose	Patch
@keystonejs/test-utils	Patch
@keystonejs/demo-project-blog	Patch
@keystonejs/demo-custom-fields	Patch
@keystonejs/demo-project-meetup	Patch
@keystonejs/demo-project-todo	Patch
@keystonejs/cypress-project-access-control	Patch
@keystonejs/cypress-project-basic	Patch
@keystonejs/cypress-project-client-validation	Patch
@keystonejs/cypress-project-login	Patch
@keystonejs/cypress-project-social-login	Patch
@keystonejs/benchmarks	Patch
@keystonejs/example-projects-blank	Patch
@keystonejs/example-projects-nuxt	Patch
@keystonejs/example-projects-starter	Patch
@keystonejs/example-projects-todo	Patch
@keystonejs/app-admin-ui	Patch
@keystonejs/app-graphql-playground	Patch
@keystonejs/app-graphql	Patch
@keystonejs/auth-passport	Patch
@keystonejs/auth-password	Patch

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[molomby]

Looks fine to me

[MadeByMike]

I like it