ci: Switch to CI image v0.28.4

This commit updates the CI workflows to use the CI image v0.28.4, which
includes Zephyr SDK 0.17.4.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>

Author: stephanosio

.github/workflows/bsim-tests.yaml

@@ -42,7 +42,7 @@ jobs:
     runs-on:
       group: zephyr-runner-v2-linux-x64-4xlarge
     container:
-      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.1.20250624
+      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.4.20250818
       options: '--entrypoint /bin/bash'
     env:
       ZEPHYR_TOOLCHAIN_VARIANT: zephyr

.github/workflows/clang.yaml

@@ -18,7 +18,7 @@ jobs:
     runs-on:
       group: zephyr-runner-v2-linux-x64-4xlarge
     container:
-      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.1.20250624
+      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.4.20250818
       options: '--entrypoint /bin/bash'
     strategy:
       fail-fast: false

.github/workflows/codecov.yaml

@@ -17,7 +17,7 @@ jobs:
     runs-on:
       group: zephyr-runner-v2-linux-x64-4xlarge
     container:
-      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.1.20250624
+      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.4.20250818
       options: '--entrypoint /bin/bash'
     strategy:
       fail-fast: false

.github/workflows/errno.yml

@@ -14,7 +14,7 @@ jobs:
   check-errno:
     runs-on: ubuntu-24.04
     container:
-      image: ghcr.io/zephyrproject-rtos/ci:v0.28.2
+      image: ghcr.io/zephyrproject-rtos/ci:v0.28.4
 
     steps:
       - name: Apply container owner mismatch workaround

.github/workflows/footprint-tracking.yml

@@ -28,7 +28,7 @@ jobs:
       group: zephyr-runner-v2-linux-x64-4xlarge
     if: github.repository_owner == 'zephyrproject-rtos'
     container:
-      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.1.20250624
+      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.4.20250818
       options: '--entrypoint /bin/bash'
     defaults:
       run:

.github/workflows/twister.yaml

@@ -127,7 +127,7 @@ jobs:
     needs: twister-build-prep
     if: needs.twister-build-prep.outputs.size != 0
     container:
-      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.1.20250624
+      image: ghcr.io/zephyrproject-rtos/ci-repo-cache:v0.28.4.20250818
       options: '--entrypoint /bin/bash'
     strategy:
       fail-fast: false