Chore: Add Recent Demo Apps to Tech Stack List of Examples

[nelsonic]

A lot of good work has been done in the last few months by @LuchoTurtle 🎉
We need to link to it from the https://github.com/dwyl/technology-stack#beginner-tutorials section of the README.md.
Currently:
https://github.com/dwyl/technology-stack/tree/178d5ebfc864274555b9be33d8988482ac140844#beginner-tutorials

Todo

• Comb through all the examples/demos/tutorials we have created in the last few months
  e.g:

1. https://github.com/dwyl/phoenix-liveview-realtime-cursor-tracking-tutorial
2. https://github.com/dwyl/flutter-phoenix-channels-demo
3. https://github.com/dwyl/learn-payment-processing
4. Hits: https://github.com/dwyl/hits fully working app we use every day to track page views in our GitHub projects.
5. Labels: https://github.com/dwyl/labels we use this to sync labels to new GitHub projects.
6. there are more. please list them all!

• Link to them from the tutorials section.
• Create a PR
• Assign for review

This is a T25min "admin" task that can be done at any time but ideally soon. 🙏
The idea is to showcase the number of tutorials we have.

Context

I recently read a post on HN with some twit complaining
about the lack of up-to-date tutorials for learning Phoenix and LiveView
I feel that we have systematically addressed it and there is no longer an excuse to not learn.

Next time someone complains, I will remind them that all our 10+ Phoenix + LiveView tutorials are up-to-date
and link directly to this list in the Tech Stack repo. 👌