chore(deps): update dependency openvox-agent to v8.15.0-1+ubuntu24.04 (#11)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

build_versions.yaml

@@ -2,4 +2,4 @@
 include:
   - release: 8
     # renovate: depName=openvox-agent openVoxRelease=8
-    agent_version: "8.14.0-1+ubuntu24.04"
+    agent_version: "8.15.0-1+ubuntu24.04"