Increase version number for ESMValCore v2.8.0rc2 (#1973)

Author: Rémi Kazeroni

CITATION.cff

@@ -188,11 +188,11 @@ authors:
     orcid: "https://orcid.org/0000-0002-5317-1247"
 
 cff-version: 1.2.0
-date-released: 2023-03-03
+date-released: 2023-03-17
 doi: "10.5281/zenodo.3387139"
 license: "Apache-2.0"
 message: "If you use this software, please cite it using these metadata."
 repository-code: "https://github.com/ESMValGroup/ESMValCore/"
 title: ESMValCore
-version: "v2.8.0rc1"
+version: "v2.8.0rc2"
 ...