chore(deps): update dependency flask to v3

pactflow-renovate-bot[bot] · JP-Ellis · commit 6735d850d706 · 2025-06-25T20:44:09.000+10:00
diff --git a/requirements.txt b/requirements.txt
@@ -1,4 +1,4 @@
-Flask==2.3.3
+Flask==3.1.1
 pytest==6.2.5
 requests==2.32.4
 pact_python==2.3.1
