Update dependency flask-babel to v4

Author: renovate[bot]

api/pyproject.toml

@@ -13,7 +13,7 @@ flask = "^1.1.4"
 launchdarkly-server-sdk = "^8.3.0"
 python-dotenv = "^1.0.1"
 sentry-sdk = "^2.0.0"
-flask-babel = "2.0.0"
+flask-babel = "4.0.0"
 flask-jwt-oidc = "^0.7.0"
 gunicorn = "^22.0.0"
 sbc-common-components = {git = "https://github.com/bcgov/sbc-common-components.git", rev = "master", subdirectory = "python"}