ci: revert to container v0.26.2

Author: vChavezB

.github/workflows/samples_build.yml

@@ -9,7 +9,7 @@ on:
 jobs:
   build-read-pd:
     runs-on: ubuntu-22.04
-    container: ghcr.io/zephyrproject-rtos/ci:v0.28.2
+    container: ghcr.io/zephyrproject-rtos/ci:v0.26.2
     env:
       CMAKE_PREFIX_PATH: /opt/toolchains