Update docs about K8s version tested in CI

We've made some changes to the K8s versions tested in E2E CI, to
optimize coverage while reducing job load. Update docs accordingly.

Signed-off-by: Daniel Farrell <[email protected]>

src/content/development/building-testing/ci-maintenance/_index.en.md

@@ -69,9 +69,9 @@ The versions that should be used in CI are described below.
 CI | Kubernetes Version | Notes
 :--- | :---- | :----
 Most CI | Latest | CI should run against the latest Kubernetes version by default.
-Basic Kubernetes Support | All non-latest supported versions | One defaults-only E2E for each non-latest supported Kubernetes version.
-Full Kubernetes Support | All non-latest supported versions | Workflow to run all CI for all of the currently-supported, non-latest Kubernetes versions. Run periodically, on releases, or manually by adding the `e2e-all-k8s` label.
-Unsupported Kubernetes Cut-off | Oldest working version | One defaults-only E2E for the oldest Kubernetes version known to work with Submariner. This tests the cut-off version used by `subctl` to prevent installing Submariner in environments that are known to be unsupported.
+Full E2E | Top/bottom of supported range | Full E2E CI matrix should use the latest Kubernetes version and the oldest non-EOL Kubernetes version.
+Full Kubernetes Support | All other non-latest supported versions | Full E2E CI matrix with all non-EOL Kubernetes versions not tested in E2E-Full. Run periodically, on releases, or manually by adding the `e2e-all-k8s` label.
+Unsupported Kubernetes Cut-off | Oldest working version | E2E for the oldest Kubernetes version known to work with Submariner. This tests the cut-off version used by `subctl` to prevent installing Submariner in environments that are known to be unsupported.
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 ## Shipyard Base Image Software