Update install_developers.rst

[mavaylon1]

Motivation

What was the reasoning behind this change? Please explain the changes briefly.
This is a small update to include install the doc requirements and to move all installs into one step. Looking forward, with a change from flake8 to ruff in an upcoming PR and a change to use pytest, this tutorial will change in the near future.

How to test the behavior?

Show how to reproduce the new behavior (can be a bug fix or a new feature)

Checklist

• Did you update CHANGELOG.md with your changes?
• Have you checked our Contributing document?
• Have you ensured the PR clearly describes the problem and the solution?
• Is your contribution compliant with our coding style? This can be checked running flake8 from the source directory.
• Have you checked to ensure that there aren't other open Pull Requests for the same change?
• Have you included the relevant issue number using "Fix #XXX" notation where XXX is the issue number? By including "Fix #XXX" you allow GitHub to close issue #XXX when the PR is merged.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (65b2a7d) 91.95% compared to head (8eec9f2) 91.95%.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #1851   +/-   ##
=======================================
  Coverage   91.95%   91.95%           
=======================================
  Files          27       27           
  Lines        2661     2661           
  Branches      699      699           
=======================================
  Hits         2447     2447           
  Misses        142      142           
  Partials       72       72           

Flag	Coverage Δ
integration	70.80% <ø> (ø)
unit	84.14% <ø> (ø)

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[rly]

I think #1853 supersedes this. Please confirm and close @mavaylon1