[8.18] (backport #17978) Start all exhastive tests in parallel (#17983)

* Start all exhastive tests in parallel (#17978)

Previously the package based tests would be blocked on the pull request suite.
Given those tests MUST have be run to even get code in to a branch this results
in the exhaustive test suite taking roughly 30 mins to even start the unique
tests. In practice when we want to reproduce or test a failure in the exhaustive
suite we DONT want to be blocked on seeing the PR tests. This commit removes the
depends-on condition for the package based tests on the pull request tests. It
does not seem like any protection from doing unncessary package based tests if a
pull request test fails is worth the extra wall time in practice. This should
significantly decrease the total time needed for the exhaustive test pipeline.

(cherry picked from commit 332355d)

# Conflicts:
#	.buildkite/scripts/exhaustive-tests/generate-steps.py

* fix merge conflict

---------

Co-authored-by: Cas Donoghue <[email protected]>

Author: mergify[bot]

.buildkite/scripts/exhaustive-tests/generate-steps.py

@@ -182,36 +182,32 @@ def acceptance_docker_steps()-> list[typing.Any]:
     structure = {"steps": []}
 
     structure["steps"].append({
-        "group": "Testing Phase",
+        "group": "Pull request suite",
         "key": "testing-phase",
         **testing_phase_steps(),
     })
 
     structure["steps"].append({
             "group": "Compatibility / Linux",
             "key": "compatibility-linux",
-            "depends_on": "testing-phase",
             "steps": compat_linux_steps,
     })
 
     structure["steps"].append({
             "group": "Compatibility / Windows",
             "key": "compatibility-windows",
-            "depends_on": "testing-phase",
             "steps": [compat_windows_step(imagesuffix=windows_test_os)],
     })
 
     structure["steps"].append({
             "group": "Acceptance / Packaging",
             "key": "acceptance-packaging",
-            "depends_on": ["testing-phase"],
             "steps": acceptance_linux_steps(),
     })
 
     structure["steps"].append({
             "group": "Acceptance / Docker",
             "key": "acceptance-docker",
-            "depends_on": ["testing-phase"],
             "steps": acceptance_docker_steps(),
     })