Add SageMaker-UI DER creds endpoint patch

**Description**

* Adding `api/creds` endpoint for the Sagemaker Unified Studio user case that to fetch credentials using DomainExecutionRoleCreds profile.

**Motivation**

* SMUS extensions would require this creds to fetch the data from S3/RedShift/Glue.

**Testing Done**

* Build CE package and ran locally. Tested building the local image using BYOI

**Backwards Compatibility Criteria (if any)**

* N/A

Author: guntamb

patched-vscode/package.json

@@ -67,6 +67,7 @@
     "update-build-ts-version": "yarn add typescript@next && tsc -p ./build/tsconfig.build.json"
   },
   "dependencies": {
+    "@aws-sdk/credential-providers": "^3.388.0",
     "@microsoft/1ds-core-js": "^3.2.13",
     "@microsoft/1ds-post-js": "^3.2.13",
     "@parcel/watcher": "2.1.0",

patched-vscode/remote/package.json

@@ -3,6 +3,7 @@
   "version": "0.0.0",
   "private": true,
   "dependencies": {
+    "@aws-sdk/credential-providers": "^3.388.0",
     "@microsoft/1ds-core-js": "^3.2.13",
     "@microsoft/1ds-post-js": "^3.2.13",
     "@parcel/watcher": "2.1.0",

patched-vscode/remote/yarn.lock

@@ -30,6 +30,7 @@ import { IProductConfiguration } from 'vs/base/common/product';
 import { isString } from 'vs/base/common/types';
 import { CharCode } from 'vs/base/common/charCode';
 import { IExtensionManifest } from 'vs/platform/extensions/common/extensions';
+import { fromIni } from "@aws-sdk/credential-providers"
 
 const textMimeType: { [ext: string]: string | undefined } = {
 	'.html': 'text/html',
@@ -103,6 +104,7 @@ export class WebClientServer {
 	private readonly _webExtensionRoute: string;
 	private readonly _idleRoute: string;
 	private readonly _envMetadata: string;
+	private readonly _derCreds: string;
 
 	constructor(
 		private readonly _connectionToken: ServerConnectionToken,
@@ -120,6 +122,7 @@ export class WebClientServer {
 		this._webExtensionRoute = `${serverRootPath}/web-extension-resource`;
 		this._idleRoute = '/api/idle';
 		this._envMetadata = '/api/env';
+		this._derCreds = '/api/creds';
 	}
 
 	/**
@@ -151,6 +154,9 @@ export class WebClientServer {
 			if (pathname === this._envMetadata) {
 				return this._handleEnvMetadata(req, res);
 			}
+			if (pathname === this._derCreds) {
+				return this._handleDERCreds(req, res);
+			}
 
 			return serveError(req, res, 404, 'Not found.');
 		} catch (error) {
@@ -507,6 +513,29 @@ export class WebClientServer {
 			serveError(req, res, 500, error.message);
 		}
 	}
+
+	/**
+	 * Handles API requests to retrieve the /opt/ml/metadata/resource-metadata.json file.
+	 */
+	private async _handleDERCreds(req: http.IncomingMessage, res: http.ServerResponse): Promise<void> {
+		try {
+			const derCreds = await fromIni({
+				profile: "DomainExecutionRoleCreds"
+			})();
+			const creds = {
+				access_key: derCreds.accessKeyId,
+				secret_key: derCreds.secretAccessKey,
+				session_token: derCreds.sessionToken
+			};
+			res.statusCode = 200;
+			res.setHeader('Content-Type', 'application/json');
+			res.setHeader('Cache-Control', 'no-store');
+			res.setHeader('Expires', '0');
+			res.end(JSON.stringify(creds));
+		} catch (error) {
+			serveError(req, res, 500, error.message);
+		}
+	}
 }
 
 /**