fix: requirements.txt to reduce vulnerabilities
fix: requirements.txt to reduce vulnerabilities


The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-DJANGO-571013
- https://snyk.io/vuln/SNYK-PYTHON-DJANGO-571014

wevote/WeVoteServer,wevote/WeVoteServer,wevote/WeVoteServer,wevote/WeVoteServer