fix: rootfs/usr/local/lib/web/backend/requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-CERTIFI-3164749
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-1014645
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-1533435
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-559452
- https://snyk.io/vuln/SNYK-PYTHON-WERKZEUG-3319935
- https://snyk.io/vuln/SNYK-PYTHON-WERKZEUG-3319936

rootfs/usr/local/lib/web/backend/requirements.txt

@@ -1,5 +1,5 @@
 backports.ssl-match-hostname==3.7.0.1
-certifi==2019.9.11
+certifi==2022.12.7
 chardet==3.0.4
 Click==7.0
 Flask==1.1.1
@@ -14,6 +14,6 @@ MarkupSafe==1.1.1
 meld3==2.0.0
 requests==2.22.0
 six==1.12.0
-urllib3==1.25.6
+urllib3==1.26.5
 websocket-client==0.47.0
-Werkzeug==0.16.0
+Werkzeug==2.2.3