Remove 8.previous from CIs tests.

Author: mashhurs

.buildkite/pull-request-test-matrix.yml

@@ -3,13 +3,9 @@
 #  and they do not break CI which jobs generator validates the release/snapshot when generating the CI steps
 8.x:
   releases:
-    - 8.previous
     - 8.current
   snapshots:
-    - 8.previous
     - 8.current
-    - 8.next
-    - 8.future
 9.x:
   releases:
     - 9.previous

.buildkite/scripts/e2e-pipeline/generate-steps.py

@@ -38,7 +38,7 @@ def generate_steps_for_scheduler(versions) -> list:
     steps: list = []
     snapshots = versions["snapshots"]
     for snapshot_version in snapshots:
-        if snapshots[snapshot_version] is None or snapshots[snapshot_version].startswith("7."):
+        if snapshots[snapshot_version] is None or snapshots[snapshot_version].startswith("7.") or snapshot_version == '8.previous':
             continue
         full_stack_version = snapshots[snapshot_version]
         version_parts = snapshots[snapshot_version].split(".")