Update tests/performance/performance_tests.sh

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: n0nag0n

tests/performance/performance_tests.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
-URL="http://firefly74.com/flight-test/test-static"
+# Allow URL to be set via environment variable or first command-line argument, default to localhost for safety
+URL="${URL:-${1:-http://localhost:8080/test-static}}"
 REQUESTS=1000
 CONCURRENCY=10
 ITERATIONS=10