chore(dependabot): limit LTS branches to patch updates

This change adjusts the Dependabot settings for the LTS branches such
that Dependabot does not open pull requests for changes which anything
more substantial than patch updates (typically security fixes).

Change-Id: Icc203038e8069e723926849a33c3e8784b544053
Signed-off-by: Chris Kay <chris.kay@arm.com>
diff --git a/changelog.yaml b/changelog.yaml
index 90f7425..422b9da 100644
--- a/changelog.yaml
+++ b/changelog.yaml
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2021-2024, Arm Limited. All rights reserved.
+# Copyright (c) 2021-2025, Arm Limited. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -1418,6 +1418,9 @@
     scope: tools
 
     subsections:
+      - title: Dependabot
+        scope: dependabot
+
       - title: STM32 Image
         scope: stm32image
 
@@ -1477,6 +1480,9 @@
       - title: Compiler runtime libraries
         scope: compiler-rt
 
+      - title: Development dependencies
+        scope: dev-deps
+
       - title: libfdt
         scope: libfdt