Fix command example-queries (remove tmp files)

The command `example-queries` needs a temporary file for each query
result. Due to a bug, only the last of these was deleted so far. Now all
of them are deleted, unless the log level is `DEBUG`.

src/qlever/commands/example_queries.py

@@ -227,6 +227,10 @@ def execute(self, args) -> bool:
                 except Exception as e:
                     error_msg = str(e)
 
+            # Remove the result file (unless in debug mode).
+            if args.log_level != "DEBUG":
+                Path(result_file).unlink(missing_ok=True)
+
             # Print description, time, result in tabular form.
             if (len(description) > 60):
                 description = description[:57] + "..."
@@ -262,6 +266,4 @@ def execute(self, args) -> bool:
                 log.info(colored("All queries failed", "red"))
 
         # Return success (has nothing to do with how many queries failed).
-        if args.log_level != "DEBUG":
-            Path(result_file).unlink(missing_ok=True)
         return True