docs(power): update createClassSerdesWithDates example to use no-arg constructor

[TrickSumo]

Issue

The createClassSerdesWithDates function requires a no-argument constructor (new () => T) as defined in the SDK type signature:

export declare function createClassSerdesWithDates<T extends object>(
  cls: new () => T,  // zero-argument constructor required
  dateProps: string[]
): Serdes<T>;

The JSDoc also explicitly states: "The class constructor (must have no required parameters)"

The current example uses a constructor with 3 required parameters, which causes a TypeScript compile error:

Argument of type 'typeof User' is not assignable to parameter of type 'new () => User'.
Target signature provides too few arguments. Expected 3 or more, but got 0.

Description of changes:

Updated createClassSerdesWithDates example to use no-arg constructor.

[yaythomas]

nice, thank you so much @TrickSumo!