Rector v1

Expands Rector version to support 1.x.

What's Changed

• chore(deps): update rector/rector requirement from ^0.19.0 to ^1.0.0 by @dependabot in #123
• docs: update Note markdown style by @kenjis in #124
• Rector Version by @MGatner in #125

Full Changelog: v1.2.0...v1.2.1