src/vs/platform/extensionManagement/node/extensionManagementService.ts/ExtensionManagementService/updateMetadata
class ExtensionManagementService:	async updateMetadata(local: ILocalExtension, metadata: IGalleryMetadata): Promise<ILocalExtension> {
		this.logService.trace('ExtensionManagementService#updateMetadata', local.identifier.id);
		local = await this.extensionsScanner.saveMetadataForLocalExtension(local, { ...((<ILocalExtensionManifest>local.manifest).__metadata || {}), ...metadata });
		this.manifestCache.invalidate();
		return local;
	}