docs(cli): note that python-web-demo support is in progress

Remove following InsightSoftwareConsortium#905.

src/itk-wasm-cli.js

@@ -299,7 +299,7 @@ program
   .requiredOption('-p, --package-name <package-name>', 'Output a package configuration files with the given packages name')
   .requiredOption('-d, --package-description <package-description>', 'Description for package')
   .option('-v, --package-version <package-version>', 'Package version, e.g. "1.0.0"')
-  .addOption(new Option('--interface <interface>', 'interface to generate bindings for, defaults to "typescript"').choices(['typescript', 'python', 'python-web-demo']))
+  .addOption(new Option('--interface <interface>', 'interface to generate bindings for, defaults to "typescript". "python-web-demo" support is in progress.').choices(['typescript', 'python', 'python-web-demo']))
   .option('-r, --repository <repository-url>', 'Source code repository URL')
   .option('-j, --js-module-url <js-module-url>', 'URL for the default hosted itk-wasm bindgen JS ESM module bundle. A JsDeliver is assumed by default.')
   .usage('[options]')