Add rust function validation - for this branch only for now

Author: otheriault

.github/workflows/validate-rust-functions.yml

@@ -0,0 +1,53 @@
+name: Validate Rust Functions
+
+on:
+  push:
+    branches: ["ot.functions-examples"]
+  pull_request:
+    branches: ["main"]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  checks:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        project:
+          - functions-local-pickup-delivery-option-generators-rs
+          - functions-pickup-point-delivery-option-generators-rs
+          - functions-location-rules-rs
+          - functions-fulfillment-constraints-rs
+          - functions-discount-rs
+          - functions-shipping-discounts-rs
+          - functions-product-discounts-rs
+          - functions-order-discounts-rs
+          - functions-discounts-allocator-rs
+          - functions-payment-customization-rs
+          - functions-delivery-customization-rs
+          - functions-cart-transform-rs
+          - functions-cart-checkout-validation-rs
+    steps:
+      - uses: actions/checkout@v3
+      - name: Add rustfmt and clippy
+        run: rustup component add rustfmt clippy
+      - name: Install node dependencies
+        run: yarn
+      - name: Expand liquid for ${{ matrix.project }}
+        working-directory: ./${{ matrix.project }}
+        run: CI=1 yarn expand-liquid .
+      - name: Run cargo fmt for ${{ matrix.project }}
+        working-directory: ./${{ matrix.project }}
+        run: cargo fmt --check
+      - name: Run clippy for ${{ matrix.project }}
+        working-directory: ./${{ matrix.project }}
+        run: cargo clippy -- -D warnings
+      - name: Run tests for ${{ matrix.project }}
+        working-directory: ./${{ matrix.project }}
+        run: cargo test
+      - name: Add wasm32-wasip1 target
+        run: rustup target add wasm32-wasip1
+      - name: Build ${{ matrix.project }} with wasm32-wasip1 target
+        working-directory: ./${{ matrix.project }}
+        run: cargo build --release --target wasm32-wasip1