news item and release-notes if relevant for 5.1.3

Signed-off-by: Håvard Ottestad <hmottestad@gmail.com>

Author: hmottestad

site/content/news/rdf4j-513.md

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+---
+title: "RDF4J 5.1.3 released"
+date: 2025-04-15T15:24:42+0200
+layout: "single"
+categories: ["news"]
+---
+RDF4J 5.1.3 is now available. This is a patch release fixing 6 bugs.
+
+For more details, have a look at the [release notes](/release-notes/5.1.3).
+<!--more-->
+### Links
+
+- [Download RDF4J](/download/)
+- [release notes](/release-notes/5.1.3).

site/content/release-notes/5.1.3.md

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+---
+title: "5.1.3"
+toc: true
+---
+RDF4J 5.1.3 is a patch release that fixes 6 issues.
+
+For a complete overview, see [all issues fixed in 5.1.3](https://github.com/eclipse/rdf4j/milestone/118?closed=1).
+
+### Acknowledgements
+
+This release was made possible by contributions from ???