add nightly 3.6 run (#340)

.github/workflows/ci.yaml

@@ -9,7 +9,7 @@ concurrency:
 on:
   pull_request:
   schedule:
-    - cron: '53 0 * * *' # Daily at 00:53 UTC
+    - cron: "53 0 * * *" # Daily at 00:53 UTC
   # Triggered on push to branch "main" by .github/workflows/release.yaml
   workflow_call:
 
@@ -66,7 +66,17 @@ jobs:
       path-to-charm-directory: ${{ matrix.path }}
 
   integration-test:
-    name: Integration test charm | 3.5.3
+    strategy:
+      fail-fast: false
+      matrix:
+        juju:
+          # This runs on all runs
+          - agent: 3.5.3 # renovate: juju-agent-pin-minor
+            allure_report: true
+          # This runs only on scheduled runs, DPW 21 specifics (scheduled + 3.6/X)
+          - snap_channel: 3.6/beta
+            allure_report: false
+    name: Integration test charm | ${{ matrix.juju.agent || matrix.juju.snap_channel }}
     needs:
       - lint
       - unit-test
@@ -76,8 +86,9 @@ jobs:
       artifact-prefix: packed-charm-cache-true
       cloud: microk8s
       microk8s-snap-channel: 1.29-strict/stable
-      juju-agent-version: 3.5.3 # renovate: juju-agent-pin-minor
-      _beta_allure_report: true
+      juju-agent-version: ${{ matrix.juju.agent }}
+      juju-snap-channel: ${{ matrix.juju.snap_channel }}
+      _beta_allure_report: ${{ matrix.juju.allure_report }}
     permissions:
       contents: write # Needed for Allure Report beta
     secrets: