[Bug]: Multiple Event Listeners Accumulation in CheckSessionService

[jagipas]

Version

18.0.1

Please provide a link to a minimal reproduction of the bug

No response

Please provide the exception or error you saw

## Description
The `CheckSessionService` is accumulating multiple event listeners for the 'message' event, causing the `messageHandler` to be executed multiple times for each event. This issue appears to have been introduced in PR #1735.

- Each time `bindMessageEventToIframe()` is called, a new event listener is added to `defaultView` without removing the previous one.
- This results in multiple executions of the `messageHandler` for a single 'message' event.
- The problem worsens over time as more listeners accumulate.

Steps to reproduce the behavior

1. Initialize the `CheckSessionService`.
2. Call `bindMessageEventToIframe()` multiple times (this may happen implicitly through other service methods).
3. Observe that 'message' events trigger multiple executions of the `messageHandler`.

A clear and concise description of what you expected to happen.

- Only one event listener should be active at any given time.
- When `bindMessageEventToIframe()` is called, it should remove any existing listener before adding a new one.

Additional context

Possible Solution

Modify the bindMessageEventToIframe() method to remove the existing listener before adding a new one:

private bindMessageEventToIframe(configuration: OpenIdConfiguration): void {
  const defaultView = this.document.defaultView;

  // Remove existing listener if there is one
  if (this.iframeMessageEventListener && defaultView) {
    defaultView.removeEventListener('message', this.iframeMessageEventListener, false);
  }

  // Create and assign the new listener
  this.iframeMessageEventListener = this.messageHandler.bind(
    this,
    configuration
  );

  if (defaultView) {
    defaultView.addEventListener(
      'message',
      this.iframeMessageEventListener,
      false
    );
  }
}