import fail on readthedocs

The autodocs is failing to import barni modules when it is compiled on readthedocs. The documentation builds correctly locally with `make html` command.

`WARNING: [autosummary] failed to import 'barni._architecture': no module named barni._architecture
WARNING: [autosummary] failed to import 'barni._bins': no module named barni._bins
WARNING: [autosummary] failed to import 'barni._class': no module named barni._class
WARNING: [autosummary] failed to import 'barni._fe': no module named barni._fe
WARNING: [autosummary] failed to import 'barni._id': no module named barni._id
WARNING: [autosummary] failed to import 'barni._label': no module named barni._label
WARNING: [autosummary] failed to import 'barni._math': no module named barni._math
WARNING: [autosummary] failed to import 'barni._peak': no module named barni._peak
WARNING: [autosummary] failed to import 'barni._plot': no module named barni._plot
WARNING: [autosummary] failed to import 'barni._reader': no module named barni._reader
WARNING: [autosummary] failed to import 'barni._roi': no module named barni._roi
WARNING: [autosummary] failed to import 'barni._sensor': no module named barni._sensor
WARNING: [autosummary] failed to import 'barni._smoothing': no module named barni._smoothing
WARNING: [autosummary] failed to import 'barni._spa': no module named barni._spa
WARNING: [autosummary] failed to import 'barni._spectrum': no module named barni._spectrum`

Start by comparing the Read the Docs build with the local `make html` command, focusing on the autodocs/autosummary import warnings for the listed `barni` modules. Done means the documentation builds on Read the Docs without the reported failed-import warnings.

Written by the indexing model from the issue text.