Updated pipelines to include Juju3

.github/workflows/ci.yaml

@@ -29,6 +29,9 @@ jobs:
         run: tox run -e lint
 
   unit-test:
+    strategy:
+      matrix:
+        juju-version:  ["2.9", "3.1"]
     name: Unit test charm
     runs-on: ubuntu-latest
     timeout-minutes: 5
@@ -41,6 +44,10 @@ jobs:
           pipx install poetry
       - name: Run tests
         run: tox run -e unit
+        env:
+          # This env var is only to indicate Juju version to "simulate" in the unit tests
+          # No libjuju is being actually used in unit testing
+          LIBJUJU_VERSION_SPECIFIER: ${{ matrix.juju-version }}
       - name: Upload Coverage to Codecov
         uses: codecov/codecov-action@v3
 
@@ -112,7 +119,7 @@ jobs:
         include:
           - juju-snap-channel: "3.1/stable"
             agent-version: "3.1.6"
-            libjuju-version:  "3.2.0.1"
+            libjuju-version:  "3.2.2"
           - juju-snap-channel: "2.9/stable"
             agent-version: "2.9.45"
             libjuju-version:  "2.9.44.1"
@@ -135,6 +142,11 @@ jobs:
         uses: charmed-kubernetes/actions-operator@main
         with:
           provider: lxd
+          bootstrap-options: "--agent-version ${{ matrix.agent-version }}"
+          juju-channel: ${{ matrix.juju-snap-channel }}
+      - name: Update python-libjuju version
+        if: ${{ matrix.libjuju-version == '2.9.44.1' }}
+        run: poetry add --lock --group integration juju@'${{ matrix.libjuju-version }}'
       - name: Download packed charm(s)
         uses: actions/download-artifact@v3
         with:
@@ -152,3 +164,5 @@ jobs:
           fi
       - name: Run integration tests
         run: tox run -e integration -- "${{ matrix.groups.path_to_test_file }}" --group="${{ matrix.groups.group_number }}" -m '${{ steps.select-test-stability.outputs.mark_expression }}' --mysql-router-charm-series=${{ matrix.ubuntu-versions.series }} --mysql-router-charm-bases-index=${{ matrix.ubuntu-versions.bases-index }}
+        env:
+          LIBJUJU_VERSION_SPECIFIER: ${{ matrix.libjuju-version }}