Update list of Copyright years

Author: rlaboiss

README.md

@@ -137,7 +137,7 @@ Thanks to [Justin Mayer][] for helping migrate of this plugin under the Pelican
 Author
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-Copyright (C) 2015, 2021-2024  Rafael Laboissière (<rafael@laboissiere.net>)
+Copyright (C) 2015, 2021-2025  Rafael Laboissière (<rafael@laboissiere.net>)
 
 License
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