Add release workflow for desync project.

.github/workflows/desync.yml

@@ -0,0 +1,41 @@
+name: Validate
+
+on:
+  push:
+    # Always run when there are new commits
+    branches:
+      - '**'
+  # Always run when there are pull requests
+  pull_request:
+    branches:
+      - '**'
+
+jobs:
+  build:
+    name: Validate on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ ubuntu-latest, windows-latest, macos-latest ]
+
+    timeout-minutes: 10
+    steps:
+      - name: Checkout desync
+        uses: actions/checkout@v2
+        with:
+          repository: V-Sekai/desync
+          fetch-depth: 0
+
+      - uses: actions/setup-go@v2
+        with:
+          go-version: '^1.15.6'
+
+      - uses: actions/cache@v1
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - run: go test
+      - run: go build ./cmd/desync