[Improvement] Add a way to disable default/base config branch policies

[gerardog]

It is confusing that there is a set of "secret" default branch policies that cant be easily removed.
Re: #3735

This is my gitversion file

mode: Mainline
branches:
  master:
    regex: '^master$|^main$'  
  other:
    mode: ContinuousDelivery
    regex: '^(?!master$|^main$/).*$'  # All branches except main, master
    tag: '{BranchName}'               # Shall have a prerelease tag based on the branch name.
    source-branches: ['main', 'master']
    increment: patch

... and I dont expect it to throw 'Multiple branch configurations match the current branch' warning because there are 6 implied default policies I need to delete: develop, release, feature, pull-request, hotfix and support
... and that I discovered by chance while diagnosing this warning message, when I ran /showconfig

If I create a branch that matches any of those 6 branch policies regex, while also matching my other, it will throw the error.
This problem was triggered when someone pushed a branch with a naming that matched both policies, like feature/something

The warning break the pipeline as described in #3735

Detailed Description

Context

So I don't have to clutter my gitversion with disabling 6 policies, which i dont know how to do btw. Shall I put bad regex to all of them?.

Possible Implementation

Either:

• I don't like the idea of a implied (and so large) base config. But I guess remove that is really breaking.
• Add a config to avoid loading base config branch policies:
• if the branch regex matches only one user-config policy, dont throw the warning even if it also matches a base-config policy
• fix the error message [Bug] Unable to suppress "Multiple branch configurations match the current branch"  #3735 Multiple branch configurations match the current branch

[HHobeck]

This feature is available since the beta-1 version of git version. The documentation says for the usage of the following property:

workflow

The base template of the configuration to use. Possible values are: GitFlow/v1 or GitHubFlow/v1

If you specify this property to an empty string you do not have any base configuration. Please see also:

• [Feature] Introducing a new templating mechanism to support different workflows #3305

Happy branching!

[gerardog]

Adding workflow: '' does solve the issue but it is undocumented except in the PR itself.
Would you please document workflow at https://gitversion.net/docs/reference/configuration ?