Instructions on how to run localstack as a service

Hi!

Thanks for creating an maintaining this!

When setting up localstack, the action spends around 60 seconds on setup. This seems excessive, and most of the time seems to go to:

• installing python dependencies
• pulling a docker image

but docker actions supports running docker images as services directly. Is this possible? If so, wouldn't that be preferrable?

此 issue 涉及 GitHub Actions workflow、Docker 服務容器以及 Python 相依套件的安裝；請先檢查 action 目前如何執行這些設定步驟。將此行為與 GitHub Actions 對 Docker 服務映像的支援進行比較，並將完成定義為：記錄或啟用一種能處理已回報啟動額外負擔的服務型設定。