feat(ci): add GitHub Action to test codegen (#1684)

* chore: remove .travis.yml

* feat(ci): add GitHub Action to run test codegen

* fix(ci): run gradle from codegen folder

* chore: break run scripts to multiple lines

.github/workflows/codegen-ci.yml

@@ -0,0 +1,35 @@
+name: codegen-ci
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    name: Java ${{ matrix.java }}
+    strategy: 
+      matrix:
+        java: [8, 11] 
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set up JDK ${{ matrix.java }}
+        uses: actions/setup-java@v1
+        with:
+          java-version: ${{ matrix.java }}
+
+      - name: build and publish smithy-typescript
+        run: |
+          git clone --depth 1 https://github.com/awslabs/smithy-typescript.git
+          cd smithy-typescript
+          ./gradlew clean build publishToMavenLocal
+          cd ..
+      
+      - name: build and test codegen
+        run: |
+          cd ./codegen
+          ./gradlew clean smithy-aws-typescript-codegen:build protocol-test-codegen:build -Plog-tests