Ignore justfile (#6941)

## Summary

Ignores justfile.

## Testing

N/A

Signed-off-by: Connor Tsui <connor.tsui20@gmail.com>

Author: connortsui20

.gitignore

@@ -219,6 +219,9 @@ profile.json.gz
 # Clang compilation database (https://clang.llvm.org/docs/JSONCompilationDatabase.html)
 compile_commands.json
 
+# Commands
+/justfile
+
 # AI Agents
 .claude
 .opencode