To PE correction warning

[cfuselli]

Gave this:

[/data/xenon/xams_v2/anaconda/xams/lib/python3.8/site-packages/numba/core/ir_utils.py:2172](https://vscode-remote+ssh-002dremote-002bnikhef.vscode-resource.vscode-cdn.net/data/xenon/xams_v2/anaconda/xams/lib/python3.8/site-packages/numba/core/ir_utils.py:2172): NumbaPendingDeprecationWarning: 
Encountered the use of a type that is scheduled for deprecation: type 'reflected list' found for argument 'adc_to_pe' of function 'sum_waveform'.

For more information visit https://numba.readthedocs.io/en/stable/reference/deprecation.html#deprecation-of-reflection-for-list-and-set-types

File "../../../software/strax/strax/processing/peak_building.py", line 171:
@numba.jit(nopython=True, nogil=True, cache=True)
def sum_waveform(peaks, hits, records, record_links, adc_to_pe, n_top_channels=0,
^

  warnings.warn(NumbaPendingDeprecationWarning(msg, loc=loc))