Add flowchart to help understand "Process Timing" vulnerability better in WSTG-BUSL-04

[RiieCco]

What would you like added?
When explaining the side-channel attack for login we can maybe add a
flowchart that helps the reader visualize the vulnerability like:

We do need to create our own image because this one i borrowed from an other example
online from this presentation:

https://slideplayer.com/slide/13837220/

Would you like to be assigned to this issue?
Check the box if you will submit a PR to add the proposed content. Please read CONTRIBUTING.md.

• Assign me, please!

[ThunderSon]

Images are always interesting. We can definitely have that.

[rejahrehim]

If this image is fine, Please suggest necessary content updates
@ThunderSon @kingthorin

[kingthorin]

• There's a typo in the bottom diamond, should be "correct".
• The arrows pointing right should have labels.
• Could you increase the spacing between the bold line and nottom-most Yes label just a bit?

[rejahrehim]

@kingthorin Updated

[kingthorin]

Nice, I like it. Thanks! I don't think there was necessarily any content updated needed in the scenario, I think this was mainly meant to help users to understand what was already there.

I believe the image is meant to accompany "Example 2"