update changelog of dCache use case

changed the date for the release of the Desy Storage (HDF) at the portal and added changelog

_posts/2022/07/2022-07-15-use-case-dCache.md

@@ -31,7 +31,7 @@ and the Nordic e-Infrastructure collaboration ([NeIC](https://neic.no/nt1/)).
 
 Thus, the system was a perfect candidate for DESY to provide mass storage Helmholtz-wide via HIFIS.
 Actually, it has been one of the first services connected to the Helmholtz AAI in early 2020 as a demonstrator.
-Now, it's becoming a regular service and will be available via the Helmholtz Cloud Portal in August 2022, branded as "DESY Storage (HDF)", HDF being short for Helmholtz Data Federation.
+Now, it's becoming a regular service and will be available via the Helmholtz Cloud Portal in autumn 2022, branded as "DESY Storage (HDF)", HDF being short for Helmholtz Data Federation.
 
 
 ## SeisBench — A toolbox for machine learning in seismology
@@ -81,3 +81,8 @@ For dCache / DESY Storage (HDF): [Christian Voss](mailto:christian.voss@desy.de?
 For SeisBench: [Jannes Münchmeyer](mailto:munchmej@gfz-potsdam.de?subject="SeisBench"), [Jack Woollam](mailto:jack.woollam@kit.edu?subject="SeisBench"), [Andreas Rietbrock](mailto:andreas.rietbrock@kit.edu?subject="SeisBench")
 
 For HIFIS: [HIFIS Support](mailto:support@hifis.net?subject="desy-storage")
+
+---
+
+#### Changelog
+- 2022-08-02 -- adapt the date for release of DESY Storage (HDF) in the Helmholtz Cloud Portal