test: check old megalodon version

packages/megalodon/src/cancel.ts

@@ -1,13 +1,13 @@
 export class RequestCanceledError extends Error {
-  public isCancel: boolean
+	public isCancel: boolean;
 
-  constructor(msg: string) {
-    super(msg)
-    this.isCancel = true
-    Object.setPrototypeOf(this, RequestCanceledError)
-  }
+	constructor(msg: string) {
+		super(msg);
+		this.isCancel = true;
+		Object.setPrototypeOf(this, RequestCanceledError);
+	}
 }
 
 export const isCancel = (value: any): boolean => {
-  return value && value.isCancel
-}
+	return value && value.isCancel;
+};