Aliaksei

Fixes for typos in C4_W3_Lab2, C4_W3_Lab3 and C4_W3_Lab4

1

- Couple of typos fixed - Readme of C4_W3_Lab_4_Github_Actions aligned with [actual workflow file](https://github.com/https-deeplearning-ai/machine-learning-engineering-for-production-public/blob/main/.github/workflows/course4-week3-lab.yml) contents