[Bandit] Lv.8 -> Lv.9

Level Goal The password for the next level is stored in the file data.txt and is the only line of text that occurs only once 1. The file had a lot of text. 2. Looking at "Commands you may need to solve this level", uniq seemed like the right fit, so I looked it up. 3. It didn't work - turns out uniq only handles duplicate lines that are adjacent to each other. Realized the lines needed to be grouped together first, and sort was the obvious choice for that. Spent 30 minutes going down the wrong path on what was actually a simple problem. 4. Yar