Flatten docs hierarchy

[alecandido]

This is just a proposal to reorganize the docs sections, in such a way that the navigation column on the left becomes more explicit and less nested (removing the need for some navigation, in the hope to make it simpler for users to consume it).

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 97.44%. Comparing base (4b8d407) to head (0fc2fdd).

Additional details and impacted files

[](https://app.codecov.io/gh/qiboteam/qibocal/pull/906?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=qiboteam) ```diff @@ Coverage Diff @@ ## main #906 +/- ## ========================================== - Coverage 97.47% 97.44% -0.04% ========================================== Files 116 116 Lines 8882 8882 ========================================== - Hits 8658 8655 -3 - Misses 224 227 +3 ``` | [Flag](https://app.codecov.io/gh/qiboteam/qibocal/pull/906/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=qiboteam) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/qiboteam/qibocal/pull/906/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=qiboteam) | `97.44% <ø> (-0.04%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=qiboteam#carryforward-flags-in-the-pull-request-comment) to find out more. [see 1 file with indirect coverage changes](https://app.codecov.io/gh/qiboteam/qibocal/pull/906/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=qiboteam)