Pin opensearch action

Author: rhysyngsun

.github/workflows/ci.yml

@@ -75,7 +75,8 @@ jobs:
           sudo sysctl -w vm.max_map_count=262144
 
       - name: Runs Opensearch
-        uses: ankane/setup-opensearch@v1
+        # pinned because versions after this drop support for opensearch 1.x
+        uses: ankane/setup-opensearch@06d8ca27e5805f1d0ad93062c0e947eab2594d64
         with:
           opensearch-version: ${{ matrix.opensearch-version }}