chore(deps): update dependency signxml to v5

Author: renovate-bot

cloud-media-livestream/keypublisher/requirements.txt

@@ -5,7 +5,7 @@ lxml==5.2.1
 pycryptodome==3.21.0
 pyOpenSSL==25.0.0
 requests==2.34.2; python_version >= '3.10'
-signxml==4.0.4
+signxml==5.0.0
 pytest==9.0.3; python_version >= "3.10"
 pytest-mock==3.14.0
 Werkzeug==3.1.8; python_version >= '3.9'