Add pip to build script

build.sh

@@ -1,6 +1,7 @@
 #!/usr/bin/env bash
 
 . ~/venv/domainaware/bin/activate
+pip install -U -r requirements.txt
 cd docs && make html && cp -r _build/html/* ../../parsedmarc-docs/
 cd ..
 rm -rf dist/ build/