add try-runtime github workflow

.github/workflows/try-runtime.yml

@@ -0,0 +1,42 @@
+name: Test storage migration
+# Test storage migration using try-runtume on PRs with label "migration"
+
+on:
+  pull_request:
+    types: [labeled, synchronize]
+  push:
+    branches: [ main ]
+
+jobs:
+  try_runtime:
+    if: contains(github.event.pull_request.labels.*.name, 'migration')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v3
+
+      - name: Setup worker
+        uses: "./.github/templates/setup-worker"
+
+      - name: Cache Build artefacts
+        uses: actions/cache/restore@v3
+        id: cargo-cache
+        with:
+          path: |
+            ~/.cargo/bin/
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            target/
+          key: ${{ runner.os }}-cargo-release-${{ env.POLKA_VERSION }}-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: ${{ runner.os }}-cargo-release-${{ env.POLKA_VERSION }}
+
+      - run: |
+          echo "Found label runtime_migration. Running tests"
+          export RUST_LOG=remote-ext=debug,runtime=debug
+          echo "---------- Running try-runtime for Trappist ----------"
+          cargo run -p trappist --locked --release --no-default-features --features trappist/trappist-runtime,try-runtime try-runtime \
+              --runtime ./target/release/wbuild/trappist-runtime/target/wasm32-unknown-unknown/release/trappist_runtime.wasm \
+              -lruntime=debug \
+              --chain=trappist-dev \
+              on-runtime-upgrade live --uri wss://rococo-trappist-try-runtime-node.parity-chains.parity.io:443