revert changes to User agent header (microsoft#138556)

Co-authored-by: Sandeep Somavarapu <[email protected]>

Author: deepak1556

src/vs/platform/extensionManagement/common/extensionGalleryService.ts

@@ -1035,8 +1035,7 @@ export async function resolveMarketplaceHeaders(version: string, productService:
 } | undefined): Promise<{ [key: string]: string; }> {
 	const headers: IHeaders = {
 		'X-Market-Client-Id': `VSCode ${version}`,
-		'X-Market-Client-Version': version,
-		'User-Agent': `VSCode (${productService.nameShort})`,
+		'User-Agent': `VSCode ${version}`
 	};
 	const uuid = await getServiceMachineId(environmentService, fileService, storageService);
 	if (supportsTelemetry(productService, environmentService) && getTelemetryLevel(configurationService) === TelemetryLevel.USAGE) {