Documenting what change we are implementing

Author: HHobeck

BREAKING_CHANGES.md

@@ -25,6 +25,7 @@
 *   A new branch related property with name `track-merge-message` has been introduced. Consider we have a `main` branch and a `release/1.0.0` branch and merge changes from `release/1.0.0` to the main branch. In this scenario the merge message will be interpreted as a next version `1.0.0` when `track-merge-message` is set to `true` otherwise `0.0.1`.
 * The pre-release tags are only considered when they are matching with the label name of the branch. This has an effect on the way how the `CommitCountSource` will be determined.
 * The process of increasing the version with bump message when `CommitMessageIncrementing` is enabled and increment strategy is `None` has been changed.
+* In the git hub and the git flow workflow the `label` property is by default set to an empty string on the `main` branch. This yields to a pre-release version on `main` with an empty tag. Instead of for instance `1.0.1+46` git-version generates the full semantic version `1.0.1-46` instead. This behavior can be changed to generate only main versions (no pre-release version) with setting the label to `null` (Please keep in mind that the `label` property on root needs to be set to `null` as well otherwise the fallback applies). This change is caused by issue #2347.
 
 ## v5.0.0