Agile model image in SDLC README not displaying


The image for the Agile Model in `resources/lecture-01/sdlc/README.md` is not showing correctly. The image link is:
```
![Agile](https://static.javatpoint.com/tutorial/software-engineering/images/software-engineering-agile-model.png)
```
Please check if the URL is valid or if the image is accessible, and update the link if necessary.