Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 6c8bee902a36e87cf2d91cbe321ca0ad4da67da4
  - Remove Ubuntu Oracular

    https://fridge.ubuntu.com/2025/07/10/ubuntu-24-10-oracular-oriole-reached-end-of-life-on-10th-july-2025/

    Change-Id: I46c3000f32738e1ea26003186ae01a5331e4b57c
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 362b200..6c8bee9 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 362b20072820bb69628311e37353d1359e2bff28
+Subproject commit 6c8bee902a36e87cf2d91cbe321ca0ad4da67da4