Merge branch 'enable_readthedocs' into 'main'

feat: adds https://docs.readthedocs.io/en/stable/config-file/v2.html

See merge request !7

.gitlab-ci.yml

@@ -15,7 +15,7 @@ build:
     - python3 -m pip install poetry --upgrade
     - make ci
 
-deploy:
+pypi:
   stage: deploy
   tags:
     - linux

.readthedocs.yaml

+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-20.04
+  tools:
+    python: "3.9"
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+   configuration: docs/source/conf.py
+
+# Optionally declare the Python requirements required to build your docs
+python:
+   install:
+   - requirements: docs/requirements.txt