message: Fixes tiny lint warnings
diff: @@ -1390,7 +1390,7 @@ export default class Sigma extends EventEmitter {
  *
  * @return {{ x: Extent, y: Extent }}
  */
  - getBBox() {
  + getBBox(): { x: Extent; y: Extent } {
  return nodeExtent(this.graph, ["x", "y"]) as { x: Extent; y: Extent };
  }
  @@ -1408,7 +1408,7 @@ export default class Sigma extends EventEmitter {
  *
  * @return {Sigma}
  */
  - setCustomBBox(customBBox: { x: Extent; y: Extent } | null) {
  + setCustomBBox(customBBox: { x: Extent; y: Extent } | null): this {
  this.customBBox = customBBox;
  this._scheduleRefresh();
  return this;
  