add 2.6.5 to compat matrix

Author: yuvalr1neo

doc/modules/ROOT/pages/installation/supported-neo4j-versions.adoc

@@ -10,6 +10,7 @@ If your version of GDS or Neo4j is not listed in the matrix, you should upgrade.
 [opts=header]
 |===
 | Neo4j version     | Neo4j Graph Data Science
+| `5.19`            | `2.7`, `2.6.5` or later
 | `5.18`            | `2.7`, `2.6.2` or later
 | `5.17`            | `2.7`, `2.6.1` or later
 | `5.16`            | `2.7`, `2.6`, `2.5.7` footnote:eol[2.5 version series is end-of-life and will not receive further patches. Please use a later version.]