fix(deps): update dependency posthog to v6

Author: renovate[bot]

poetry.lock

@@ -83,7 +83,7 @@ opentelemetry-instrumentation-redis = ">=0.52b0"
 opentelemetry-instrumentation-requests = ">=0.52b0"
 opentelemetry-sdk = ">=1.31.0"
 pluggy = "^1.3.0"
-posthog = "^5.0.0"
+posthog = "^6.0.0"
 psycopg = "^3.2.4"
 psycopg2 = "^2.9.6"
 pycountry = "^24.6.1"