Add docs/build command with --rm option (apache#210)

Add docs/build command so that we can execute the command more easily.

Author: ebyhr

README.md

@@ -83,8 +83,7 @@ Building docs
 - Docs are generated using [Redocly](https://redocly.com/docs/cli/installation). To regenerate them, run the following
 commands from the project root directory.
 ```bash
-docker run -p 8080:80 -v ${PWD}:/spec docker.io/redocly/cli join spec/docs.yaml spec/polaris-management-service.yml spec/rest-catalog-open-api.yaml -o spec/index.yaml --prefix-components-with-info-prop title
-docker run -p 8080:80 -v ${PWD}:/spec docker.io/redocly/cli build-docs spec/index.yaml --output=docs/index.html --config=spec/redocly.yaml
+docs/build
 ```
 
 ## License

docs/build

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+
+set -eux
+
+docker run -p 8080:80 -v ${PWD}:/spec --rm docker.io/redocly/cli join spec/docs.yaml spec/polaris-management-service.yml spec/rest-catalog-open-api.yaml -o spec/index.yaml --prefix-components-with-info-prop title
+docker run -p 8080:80 -v ${PWD}:/spec --rm docker.io/redocly/cli build-docs spec/index.yaml --output=docs/index.html --config=spec/redocly.yaml