github: Migrate from travis to GH actions

.github/workflows/main.yml

@@ -0,0 +1,32 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [opened, synchronize, reopened]
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    env:
+      SCYLLA_VERSION: 4.2.0
+      GOBIN: ./bin
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+      - uses: actions/cache@v2
+        id: gomod-cache
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('go.mod') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - run: mkdir -p ${GOBIN}
+      - run: make get-deps get-tools
+      - run: make check
+      - run: make run-scylla
+      - run: make test