extensions/markdown-language-features/src/languageFeatures/diagnostics.ts/InflightDiagnosticRequests/cancel
class InflightDiagnosticRequests:	public cancel(resource: vscode.Uri) {
		const existing = this.inFlightRequests.get(resource);
		if (existing) {
			existing.cts.cancel();
			this.inFlightRequests.delete(resource);
		}
	}