Fix "distribution was not found and is required by kubernetes" in CI

When running "python setup.py install" in CI, we were getting
"requests distribution was not found and is required by kubernetes"
errors. I can reproduce this issue locally. The error disappears after
the same command is run a second time.

This is a similar issue: https://github.com/pypa/setuptools/issues/498

.gitlab-ci.yml

@@ -9,7 +9,7 @@ test:
   script:
     - apk add --no-cache make
     - make ci-install-alpine-requirements
-    - python setup.py install
+    - pip install .
     - make ci-install-python-requirements
     - make test
 
@@ -17,7 +17,7 @@ build:images:
   script:
     - apk add --no-cache make
     - make ci-install-alpine-requirements
-    - python setup.py install
+    - pip install .
     - make ci-build-images
   tags:
     - private
@@ -49,7 +49,7 @@ deploy:images:
   script:
     - apk add --no-cache make
     - make ci-install-alpine-requirements
-    - python setup.py install
+    - pip install .
     - make ci-push-images
   only:
     - tags

Makefile

@@ -76,7 +76,7 @@ ci-install-alpine-requirements: ## Install requirements for a python:alpine imag
 ci-install-python-requirements: ## Install requirements
 	pip3 install --upgrade pip
 	pip3 install setuptools==44.0.0
-	python3 setup.py install
+	pip install .
 	pip3 install -r requirements/dev.txt
 
 ci-install-plugins: ci-install-python-requirements ## Install all supported plugins