changed installation order

Signed-off-by: Jürgen Eckel <juergen@riddleandcode.com>

.readthedocs.yml

@@ -3,38 +3,17 @@
 # SPDX-License-Identifier: (Apache-2.0 AND CC-BY-4.0)
 # Code is Apache-2.0 and docs are CC-BY-4.0
 
-#build:
-#    image: latest
 
-#python:
-#    version: 3.9
-#    pip_install: true
-
-
-# Required
 version: 2
 
-# Set the version of Python and other tools you might need
+
 build:
   os: ubuntu-20.04
   tools:
     python: "3.9"
-    # You can also specify other tool versions:
-    # nodejs: "16"
-    # rust: "1.55"
-    # golang: "1.17"
 
-# Build documentation in the docs/ directory with Sphinx
-#sphinx:
-#   configuration: docs/root/source/conf.py
-
-# If using Sphinx, optionally build your docs in additional formats such as PDF
-# formats:
-#    - pdf
-
-# Optionally declare the Python requirements required to build your docs
 python:
    install:
-   - requirements: docs/root/requirements.txt
    - method: setuptools
      path: .
+   - requirements: docs/root/requirements.txt