Improve error message such that it is more actionable

[nbars]

ref/ref-docker-base/task.py

Lines 158 to 159 in 309fd59

	print_err(f'[!] Test output exceeded maximum length of {MAX_TEST_OUTPUT_LENGTH} characters.')
	print_err(f'[!] You need to trim the output of your solution script(s) to submit!')

Maybe add something along those lines:

Please remove or reduce any unnecessary output (e.g., debug prints) so that all output of your solution stays within the allowed limit, and try submitting again.