Update flask requirement from ~=3.1.2 to ~=3.1.3 in /dao (#558)

Updates the requirements on [flask](https://github.com/pallets/flask) to permit the latest version.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/3.1.3/CHANGES.rst)
- [Commits](pallets/flask@3.1.2...3.1.3)

---
updated-dependencies:
- dependency-name: flask
  dependency-version: 3.1.3
  dependency-type: direct:production
...

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Author: dependabot[bot]

dao/requirements.txt

@@ -16,7 +16,7 @@ SQLAlchemy-Utils~=0.42.1
 psycopg2-binary
 pymysql~=1.1.2
 mariadb~=1.1.14
-flask~=3.1.2
+flask~=3.1.3
 ephem~=4.2
 gunicorn~=25.1.0
 cryptography~=46.0.5