* test: fix mocks

* fix(manager:npm): patch local yarn v1 binary

* refactor(config): strict null checks

* chore: fix test

* feat(datasource/crate): fetch crate metadata from crates.io

* refactor(datasource/crate): simplify `mockCratesApiCallFor()` function

Co-authored-by: Rhys Arkins <rhys@arkins.net>

Co-authored-by: Rhys Arkins <rhys@arkins.net>

Moves datasource, manager, platform and versioning code from lib/ into new lib/modules/

BREAKING CHANGE: External tools must update paths to datasource, manager, platform and versioning

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

Co-authored-by: Jamie Magee <jamie.magee@gmail.com>

* refactor: introduce Fixtures util class

* refactor: align yarn.spec

* refactor: move fs mocks to __mocks__ folder

* refactor: improve fs-extra mock

* refactor: move callsite to dev deps

* refactor: use fixtures class

* refactor: use fixtures class

* refactor: reduce external variables in tests

* refactor: improve Fixtures

* refactor: add type for realFs

* refactor: remove obsolete snapshot

* fix: by comments

* refactor: provide ability to spy on mocked fs methods

* refactor: fix build

* refactor: fix by comments

* refactor: add docs

* refactor: fix unit test

* refactor: return called times checks

* refactor: fix by comments

* refactor: adjust unit test

* refactor: adjust unit test

* refactor: fix unit test

* refactor: fix by comments

* refactor: fix by comments

* refactor: update jsdoc

* refactor: fix by comments

Co-authored-by: Rhys Arkins <rhys@arkins.net>
Co-authored-by: Jamie Magee <jamie.magee@gmail.com>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

* refactor(migrations): implemented migration validator

* refactor(migrations): introduce deprecated flag

* refactor(migrations): tidy

* refactor(migrations): improve validator

* refactor: fix launch.json

* refactor: fix build

* refactor: fix coverage

* refactor: fix coverage

* refactor: introduce new jest custom matcher

* refactor: revert unnecessary changes

* refactor: return override

* refactor: prepare esm helper

* chore: fix type name

Co-authored-by: Rhys Arkins <rhys@arkins.net>

Co-authored-by: Rhys Arkins <rhys@arkins.net>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

Co-authored-by: Rhys Arkins <rhys@arkins.net>

Co-authored-by: Rhys Arkins <rhys@arkins.net>

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Co-authored-by: Rhys Arkins <rhys@arkins.net>

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

Co-authored-by: Renovate Bot <bot@renovateapp.com>
Co-authored-by: Rhys Arkins <rhys@arkins.net>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>