build: bump build-images for eMudhra ca-certificates removal (#55187)

build: bump build-images to pick up eMudhra ca-certificates removal

Point the build image pin at the image built from electron/build-images#106,
which installs jammy's ca-certificates 20260816ubuntu0.22.04.1 (USN-8944-1)
dropping the eMudhra "emSign ECC Root CA - G3" root.


Claude-Session: https://claude.ai/code/session_01Kpt4TnMMYe362XSUYdQNnF

Co-authored-by: Claude <noreply@anthropic.com>

.devcontainer/docker-compose.yml

@@ -2,7 +2,7 @@ version: '3'
 
 services:
   buildtools:
-    image: ghcr.io/electron/devcontainer:eac3529546ea8f3aa356d31e345715eef342233b
+    image: ghcr.io/electron/devcontainer:a64d60a8f35fe163b567b4968699b866646085f9
 
     volumes:
       - ..:/workspaces/gclient/src/electron:cached

.github/actions/build-image-sha/action.yml

@@ -20,5 +20,5 @@ runs:
         if [ -n "$OVERRIDE" ]; then
           echo "build-image-sha=$OVERRIDE" >> "$GITHUB_OUTPUT"
         else
-          echo "build-image-sha=daad061f4b99a0ae1c841be4aa09188280a9c8a4" >> "$GITHUB_OUTPUT"
+          echo "build-image-sha=a64d60a8f35fe163b567b4968699b866646085f9" >> "$GITHUB_OUTPUT"
         fi