message: Update texture utils
diff: -/* -------------------------------------------- */
  -
  /**
  * Test whether a file source exists by performing a HEAD request against it
  * @param src - The source URL or path to test
  */
  declare function srcExists(src: string): Promise<boolean>;
  -/* -------------------------------------------- */
  -
  /**
  * Get a single texture from the cache
  */
  @@ -18,7 +14,7 @@ declare function getTexture(src: string): PIXI.Texture | null;
  * Load a single texture and return a Promise which resolves once the texture is ready to use
  * @param src - The requested texture source
  * @param fallback - A fallback texture to use if the requested source is unavailable or invalid
  - * (default: `null`)
  + * (default: `undefined`)
  */
  declare function loadTexture(
  src: string,
  @@ -27,8 +23,8 @@ declare function loadTexture(
  }?: {
  /**
  * A fallback texture to use if the requested source is unavailable or invalid
  - * @defaultValue `null`
  + * @defaultValue `undefined`
  */
  fallback?: string;
  }
  -): Promise<PIXI.Texture | null>;
  +): Promise<PIXI.Texture>;
  