message: docs: update readme on build.postBuildCommands
diff: @@ -452,7 +452,7 @@ The fourth cache behaviour handles next API requests `api/*`.
  | build.cwd | `string` | `./` | Override the current working directory |
  | build.enabled | `boolean` | `true` | Same as passing `build:false` but from within the config |
  | build.env | `object` | `{}` | Add additional environment variables to the script |
  -| build.postBuildCommands | `Array` | `[]` | Any commands to run post-build and pre-deploy. For example, you can run any custom code on the `.serverless_nextjs` directory. Only applies during execution of the `serverless` command. |
  +| build.postBuildCommands | `Array` | `[]` | Any commands to run post-build and pre-deploy. For example, you can run any custom code on the `.serverless_nextjs` directory e.g you can copy additional files into the Lambda: see https://github.com/serverless-nextjs/serverless-next.js/issues/767#issuecomment-722967719 for an example for `next-18n`. Only applies during execution of the `serverless` command. |
  | cloudfront | `object` | `{}` | Inputs to be passed to [aws-cloudfront](https://github.com/serverless-components/aws-cloudfront) |
  | certificateArn | `string` | `` | Specific certificate ARN to use for CloudFront distribution. Helpful if you have a wildcard SSL cert you wish to use. This currently works only in tandem with the `domain` input. Please check [custom CloudFront configuration](https://github.com/serverless-nextjs/serverless-next.js#custom-cloudfront-configuration) for how to specify `certificate` without needing to use the `domain` input (note that doing so will override any certificate due to the domain input). |
  | domainType | `string` | `"both"` | Can be one of: `"apex"` - apex domain only, don't create a www subdomain. `"www"` - www domain only, don't create an apex subdomain.`"both"` - create both www and apex domains when either one is provided. |
  