Add step to release GH actions (#1792)

* feat: add a release step to nym contracts GH action

* feat: add shrinking the size of wasm

.github/workflows/contracts-build.yml

@@ -1,10 +1,8 @@
 name: Build release of Nym smart contracts
 on:
   workflow_dispatch:
-
-defaults:
-  run:
-    working-directory: contracts
+  release:
+    types: [created]
 
 jobs:
   build:
@@ -21,7 +19,7 @@ jobs:
           components: rustfmt, clippy
 
       - name: Build release contracts
-        run: RUSTFLAGS='-C link-arg=-s' cargo build --release --target wasm32-unknown-unknown
+        run: make wasm
 
       - name: Upload Mixnet Contract Artifact
         uses: actions/upload-artifact@v3
@@ -36,3 +34,11 @@ jobs:
           name: vesting_contract.wasm
           path: contracts/target/wasm32-unknown-unknown/release/vesting_contract.wasm
           retention-days: 5
+
+      - name: Upload to release based on tag name
+        uses: softprops/action-gh-release@v1
+        if: github.event_name == 'release'
+        with:
+          files: |
+            contracts/target/wasm32-unknown-unknown/release/vesting_contract.wasm
+            contracts/target/wasm32-unknown-unknown/release/mixnet_contract.wasm