fix: requirements/test_requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-FLASKCORS-7707876

requirements/test_requirements.txt

@@ -548,7 +548,7 @@ flask-babel==4.0.0 \
     --hash=sha256:638194cf91f8b301380f36d70e2034c77ee25b98cb5d80a1626820df9a6d4625 \
     --hash=sha256:dbeab4027a3f4a87678a11686496e98e1492eb793cbdd77ab50f4e9a2602a593
     # via -r webapp_requirements.in
-flask-cors==4.0.1 \
+flask-cors==5.0.0 \
     --hash=sha256:eeb69b342142fdbf4766ad99357a7f3876a2ceb77689dc10ff912aac06c389e4 \
     --hash=sha256:f2a704e4458665580c074b714c4627dd5a306b333deb9074d0b1794dfa2fb677
     # via -r webapp_requirements.in