ci: migrate to fastify reusable workflow

[Fdawgs]

Checklist

• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[mcollina]

Why is a draft?

[Fdawgs]

Why is a draft?

There's something wrong with the Postgres and MySQL reusable workflow syntax, so set these to drafts until I can sort it.

[climba03003]

Why is a draft?

There's something wrong with the Postgres and MySQL reusable workflow syntax, so set these to drafts until I can sort it.

I think it is missing a quote for the string. fastify/workflows#26

The workflow is not valid. fastify/workflows/.github/workflows/plugins-ci-mysql.yml@v3: (Line: 68, Col: 14, Idx: 1601) - (Line: 68, Col: 19, Idx: 1606): While scanning a plain scalar, find unexpected ':'. Unexpected type '' encountered while reading 'root'. The type 'MappingToken' was expected.