chore: enable CI for the experimental branch

Since the experimental branch and the main branch use different versions of SLURM, we need to use the experimental branch for `slurmctld` when pushing new changes to `slurmctld`.

.github/workflows/ci.yaml

@@ -16,6 +16,8 @@ name: slurmd charm tests
 on:
   workflow_call:
   pull_request:
+    branches:
+      - main
 
 jobs:
   inclusive-naming-check:

.github/workflows/experimental.yaml

@@ -0,0 +1,101 @@
+# Copyright 2023 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: slurmd charm tests (experimental)
+on:
+  workflow_call:
+  pull_request:
+    branches:
+      - experimental
+
+jobs:
+  inclusive-naming-check:
+    name: Inclusive naming check
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: woke
+        uses: get-woke/woke-action@v0
+        with:
+          # Cause the check to fail on any broke rules
+          fail-on-error: true
+
+  lint:
+    name: Lint
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install dependencies
+        run: python3 -m pip install tox
+      - name: Run linters
+        run: tox -e lint
+
+  type:
+    name: Type check with pyright
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install dependencies
+        run: python3 -m pip install tox
+      - name: Run pyright
+        run: tox -e type
+
+  unit-test:
+    name: Unit tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Install dependencies
+        run: python3 -m pip install tox
+      - name: Run tests
+        run: tox -e unit
+
+  integration-test:
+    strategy:
+      fail-fast: true
+      matrix:
+        bases:
+          - [email protected]
+    name: Integration tests (LXD) | ${{ matrix.bases }}
+    runs-on: ubuntu-latest
+    needs:
+      - inclusive-naming-check
+      - lint
+      - type
+      - unit-test
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          path: main
+      - name: Fetch slurmctld
+        uses: actions/checkout@v4
+        with:
+          repository: charmed-hpc/slurmctld-operator
+          path: slurmctld-operator
+          ref: experimental
+      - name: Setup operator environment
+        uses: charmed-kubernetes/actions-operator@main
+        with:
+          provider: lxd
+          juju-channel: 3.1/stable
+      - name: Run tests
+        run: |
+          cd main && tox run -e integration -- \
+             --charm-base=${{ matrix.bases }} \
+             --use-local