fix(Makefile): install pip<22 to prevent pip-tools bug

jazzband/pip-tools#1558

Author: m0wer

Makefile

@@ -6,7 +6,7 @@ install:
 	@echo "---------------------------"
 	@echo "- Installing dependencies -"
 	@echo "---------------------------"
-	python -m pip install pip-tools
+	python -m pip install "pip<22" pip-tools
 	python -m piptools sync requirements.txt docs/requirements.txt requirements-dev.txt
 	pre-commit install
 

requirements-dev.in

@@ -1,6 +1,8 @@
 -c requirements.txt
 -c docs/requirements.txt
 
+pip<22
+
 pre-commit
 pytest
 pytest-cookies

requirements-dev.txt

@@ -133,3 +133,7 @@ urllib3==1.26.7
     #   requests
 virtualenv==20.9.0
     # via pre-commit
+
+# The following packages are considered to be unsafe in a requirements file:
+pip==21.3.1
+    # via -r requirements-dev.in