Resolves #5896 - Add new Data Engineering Sub (#7993)

* Resolves #5896 - Add new Data Engineering Sub

Finally I made a new Data Engineering Sub, because the are Data Science and Machine Learning.
I think Data Engineering could be one new Sub
Resolves #5896

* Swap the ordering

Ordering correction
Resolves #5896

* Move Data Engineering into Data Science

courses/free-courses-en.md

@@ -342,12 +342,15 @@
 ### Data Science
 
 * [Advanced Data Mining with Weka MOOC](https://www.cs.waikato.ac.nz/ml/weka/mooc/advanceddataminingwithweka/)
+* [Apache Airflow Tutorials](https://www.youtube.com/playlist?list=PLYizQ5FvN6pvIOcOd6dFZu3lQqc6zBGp2) - Tuan Vu (YouTube)
 * [Applied Data Science with Python](https://cognitiveclass.ai/learn/data-science-with-python) - CognitiveClass.ai
 * [CS250: Python for Data Science](https://learn.saylor.org/course/view.php?id=504) - Saylor Academy
 * [Data Analysis and Visualization](https://www.udacity.com/course/data-analysis-and-visualization--ud404) - Georgia Tech (Udacity)
 * [Data Analysis with Python: Zero to Pandas](https://jovian.ai/learn/data-analysis-with-python-zero-to-pandas) (Jovian)
 * [Data Analysis with R](https://www.udacity.com/course/data-analysis-with-r--ud651) - Facebook (Udacity)
+* [Data Build Tool (dbt)](https://www.youtube.com/playlist?list=PLy4OcwImJzBLJzLYxpxaPUmCWp8j1esvT) - Kahan Data Solutions (YouTube)
 * [Data Cleaning](https://www.kaggle.com/learn/data-cleaning) - Rachael Tatman (Kaggle)
+* [Data Engineering](https://www.youtube.com/playlist?list=PLy4OcwImJzBKg3rmROyI_CBBAYlQISkOO) - Kahan Data Solutions (YouTube)
 * [Data Mining with Weka MOOC](https://www.cs.waikato.ac.nz/ml/weka/mooc/dataminingwithweka/)
 * [Data science for beginners](https://microsoft.github.io/Data-Science-For-Beginners) - Microsoft
 * [Data Science Fundamentals](https://cognitiveclass.ai/learn/data-science) - CognitiveClass.ai