Fix description of handling-errors lab

Signed-off-by: David A. Wheeler <[email protected]>

Author: david-a-wheeler

secure_software_development_fundamentals.md

@@ -3176,7 +3176,7 @@ Error-handling is a fact of life, but you need to make sure your error handling
 
 #### Lab: Handling Errors
 
- 🧪 Lab: Please try lab [handling-errors](https://best.openssf.org/labs/handling-errors.html), which lets you experiment in how to counter an OS shell (injection) vulnerability.
+ 🧪 Lab: Please try lab [handling-errors](https://best.openssf.org/labs/handling-errors.html), which lets you experiment with leveraging an error handling mechanism (specifically exception handling) and improve its robustness.
 Labs are optional, but we encourage you to try them.
 
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