[Auto version bump] 2026-05-29 Bump versions.json to 9.3.6 (elastic#272006)

Generated by https://buildkite.com/elastic/kibana-version-bump/builds/55

Author: kibanamachine

versions.json

@@ -12,7 +12,7 @@
       "branchType": "release"
     },
     {
-      "version": "9.3.5",
+      "version": "9.3.6",
       "branch": "9.3",
       "branchType": "release"
     },