GH-1402 - Update copyright year in index.adoc.

While reviewing the Spring Modulith project documentation, I noticed that with the latest release of version 1.4.3 (2025), the copyright year in the reference documentation has not yet been updated.

Signed-off-by: Patrick Baumgartner <contact@patbaumgartner.com>

Author: patbaumgartner

src/docs/antora/modules/ROOT/pages/index.adoc

@@ -5,7 +5,7 @@ Oliver Drotbohm
 :revdate: {localdate}
 :icons: font
 
-© 2022-2023 The original authors.
+© 2022-2025 The original authors.
 
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