Use newer Vale and markdownlint-cli versions for building linting images

To build linting images for newer versions of Vale and markdownlint-cli, we first need to set newer versions to use in CI/CD pipelines when building.

This will help upgrade:

• Vale from https://github.com/errata-ai/vale/releases/tag/v2.10.4 to: https://github.com/errata-ai/vale/releases/tag/v2.12.0.
• markdownlint-cli from https://github.com/igorshubovych/markdownlint-cli/releases/tag/v0.28.1 to https://github.com/igorshubovych/markdownlint-cli/releases/tag/v0.29.0.

CC @axil @marcel.amirault