chore: bump version nr in cff file

Author: github-actions[bot]

CITATION.cff

@@ -1,7 +1,7 @@
 cff-version: 1.2.0
 message: To cite this reposository, please use these metadata.
 title: "The Swedish Parliament Corpus: pyriksdagen"
-version: v1.8.1
+version: v1.9.0
 authors:
   - given-names: Väinö
     family-names: Yrjänäinen