Automatically trigger manual dependencies of a manual job

Let’s consider the following setup:

• A build job triggered automatically, without any dependencies.
• A test job triggered manually, needing the build job to be finished.
• A deploy job triggered manually, needing the build and test job to be finished.

The corresponding .gitlab-ci.yaml would be the following:

stages:
  - build
  - test
  - deploy

build:
  stage: build
  needs: []
  script: [...]

test:
  stage: test
  needs: [build]
  rules:
    - when: manual
      allow_failure: true
  script: [...]

deploy:
  stage: deploy
  needs: [test, build]
  rules:
    - when: manual
      allow_failure: true
  script: [...]

My issue is that if I want to trigger the deploy job, I need to

• wait for the build job to finish,
• trigger the test job manually,
• wait for the test job to finish,
• and then trigger the deploy job.

Is there any way to automatically do that by only clicking one button?
In other words, I would like to be able to trigger both test and deploy jobs all at once, even before the end of the build job, so that they turn in waiting status, and then run one after another automatically according to their dependency rules.

NB1: I know there are ways to do that with rules based on branch name, tag, commit message etc. But I really want to be able to decide to launch the deploy job (with its dependencies) from any commit in the Gitlab UI, without having to push something specific. And I also want to keep the possibility to run the test job independently from the deploy job.

NB2: My use-case is in reality much more complicated with dozens of dependent jobs, and I am looking for an easy way to manually trigger all the upstream dependencies of a manual job without having to run each stage manually one after another.