adjust git-date package size expectation

Author: Byron

etc/check-package-size.sh

@@ -40,7 +40,7 @@ echo "in root: gitoxide CLI"
 (enter git-traverse && indent cargo diet -n --package-size-limit 10KB)
 (enter git-url && indent cargo diet -n --package-size-limit 20KB)
 (enter git-validate && indent cargo diet -n --package-size-limit 5KB)
-(enter git-date && indent cargo diet -n --package-size-limit 10KB)
+(enter git-date && indent cargo diet -n --package-size-limit 15KB)
 (enter git-filter && indent cargo diet -n --package-size-limit 5KB)
 (enter git-lfs && indent cargo diet -n --package-size-limit 5KB)
 (enter git-note && indent cargo diet -n --package-size-limit 5KB)