Update the Neo4j version to 5.26.8, Java driver to 5.28.5 (#278)

Author: NataliaIvakina

antora.yml

@@ -9,9 +9,9 @@ nav:
 asciidoc:
   attributes:
     neo4j-version: '5.26'
-    neo4j-version-exact: '5.26.7'
+    neo4j-version-exact: '5.26.8'
     neo4j-buildnumber: '5.26'
-    java-driver-version: '5.28.4'
+    java-driver-version: '5.28.5'
     neo4j-documentation-branch: 'dev'
     page-origin-private: false
     neo4j-javadocs-base-uri: "https://neo4j.com/docs/java-reference/5/javadocs"