Adding a step to the CI/CD pipeline that runs a dynamic code analysis tool and a static code analysis tool during the pipeline execution helps make the security of an application a more integral part of the software development lifecycle. Dynamic code analysis tools search for coding errors and vulnerabilities while the application is running, while static code analysis tools scan the source code for potential errors and vulnerabilities. This ensures that any security issues are identified and addressed before the application is deployed. Additionally, using automated tools helps to reduce the amount of manual effort required for security testing and can reduce the risk of security flaws being introduced.

Explanation
A webhook is basically a callback URL that is triggered when certain events occur, such as a code commit. If the webhook call from the code repository does not reach the CI server, then the pipeline will not start.
According to the Cisco Implementing DevOps Solutions and Practices using Cisco Platforms (DEVOPS) Study Manual, "A webhook is a web-based feature that enables a remote service to communicate with a local service, usually through a web server. Webhooks are used to trigger an action when a specific event occurs, usually in a remote service or application."