Allow old sampler names in API

[missionfloyd]

Allows using the pre-#15333 sampler names in API requests.
Fixes #15603

Checklist:

• I have read contributing wiki page
• I have performed a self-review of my own code
• My code follows the style guidelines
• My code passes tests

[ashmuse]

@AUTOMATIC1111 Please 🙏

[shutarojp]

Can you guys, just create a option, let people want new style menu or someone just like me want the old menu back? so we can set it in option page. Thank you

[w-e-w]

I think I better fix would be a fixed inside class StableDiffusionProcessing
this way that it will apply for every instance of this issue not just API