Add GitHub action to deploy to AWS after successful build

[msailes]

Create a GitHub action to deploy the infrastructure defined in the CDK code to AWS after a successful build.

[elenavanengelenmaslova]

I can create a Pull request for this if you like, I do need the gitHub actions secret key names for
aws_access_key
aws_secret_key
aws_region
aws_account_id

its looks something like this:
`steps:
- uses: actions/checkout@v2

  - name: Download Artifacts
    uses: actions/download-artifact@v2
    with:
      name: LambdaArtifacts
      path: build/dist/

  - uses: actions/setup-node@v2
    with:
      node-version: "14"
  - name: Configure aws credentials
    uses: aws-actions/configure-aws-credentials@master
    with:
      aws-access-key-id: ${{ secrets.aws_access_key }}
      aws-secret-access-key: ${{ secrets.aws_secret_key }}
      aws-region: ${{ inputs.aws_region }}

  - name: DEPLOY synthesize & deploy
    run: |
      cd ${GITHUB_WORKSPACE}/infrastructure
      npm install -g aws-cdk
      cdk deploy`