added github action to build and push to docker

.github/workflows/build.yaml

@@ -0,0 +1,19 @@
+name: build
+on:
+  push:
+    branches:
+      - main
+jobs:
+  build:
+    runs-on: ${{ secrets.RUNNER }}
+    steps:
+      - uses: actions/checkout@master
+      - name: Build and push to Docker Hub
+        uses: docker/build-push-action@v1
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+          repository: alejoide/bcra-scraper-api
+          tag_with_ref: true
+          tag_with_sha: true
+          tags: ${{ github.sha }}