[x] Commit messages follow the project guidelines.
[x] Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
[x] New feature has been documented/Current behavior is correctly described in the documentation.
N/A: Applicable backports have been included in the description.
Reviewer Checklist
[x] The PR has a milestone assigned.
[x] The title and description correctly express the PR's purpose.
[x] Check contributor checklist is correct.
[x] Check CI results: changes do not issue any warning.
[x] Check CI results: failing tests are unrelated with the changes.
Description
This PR makes master branch become 4.0.
Contributor Checklist
Reviewer Checklist