FIX Update schema generation error link to point to latest version of documentation

[maxime-rainville]

Description

Simple update to point users to the latest version of the docs.

Issues

• SchemaBuilder outputs link to old doc on error. #634

Pull request checklist

• The target branch is correct
• All commits are relevant to the purpose of the PR (e.g. no debug statements, unrelated refactoring, or arbitrary linting)
• The commit messages follow our commit message guidelines
• The PR follows our contribution guidelines
• Code changes follow our coding conventions
• This change is covered with tests (or tests aren't necessary for this change)
• Any relevant User Help/Developer documentation is updated; for impactful changes, information is added to the changelog for the intended release
• CI is green

[GuySartorelli]

This should link to the specific docs for this version - i.e. 5 on this branch and 6 on 6.0.

[maxime-rainville]

This should link to the specific docs for this version - i.e. 5 on this branch and 6 on 6.0.

I thought we had decided to avoid including the version number when including documentation link to doc in the PHPDoc or in code? That way, every time someone follows that link, they'll be redirected to the latest version.

Otherwise, every time you do a major release, you'll have to go through all the code base and find all instances of https://docs.silverstripe.org/en/X and increment it by one.

Happy to change it if I'm misremembering this.