Add quotes to release date

cdboer · cdboer · commit 8342cdc4268a · 2022-07-18T14:20:57.000+02:00
diff --git a/CITATION.cff b/CITATION.cff
@@ -12,7 +12,7 @@ authors:
     affiliation: "German Aerospace Center (DLR)"
     orcid: "https://orcid.org/0000-0001-5750-5649"
 version: 1.1.4
-date-released: 2022-07-18
+date-released: "2022-07-18"
 license: MIT
 repository-code: "https://github.com/DLR-SC/gitlab2prov"
 references:
