Bump lxml-html-clean from 0.1.1 to 0.4.0 in /requirements #5314

Job	Run time
lint	27s
docs	7m 30s
tests (macos-13, 3.10, all)	37m 31s
check-examples (03-FFT-examples.ipynb)	3m 9s
tests (ubuntu-latest, 3.10, all)	23m 56s
check-examples (04-RNN-examples.ipynb)	7m 8s
check-examples (00-quickstart.ipynb)	8m 34s
check-examples (02-data-processing.ipynb)	3m 30s
check-examples (01-multi-time-series-and-covariates.ipynb)	6m 50s
	1h 38m 35s

Provide feedback