ci: support runner-specific jpeg packages for qemu

Author: sjmiller609

.github/workflows/test.yml

@@ -40,7 +40,22 @@ jobs:
              ! command -v iptables &> /dev/null || \
              [ "$has_libjpeg8" -eq 0 ]; then
             sudo apt-get update
-            sudo apt-get install -y erofs-utils e2fsprogs iptables libjpeg8
+            sudo apt-get install -y erofs-utils e2fsprogs iptables
+
+            # Different runner images expose JPEG libs under different package names.
+            if ! ldconfig -p | grep -q 'libjpeg\.so\.8'; then
+              sudo apt-get install -y libjpeg-turbo8 || sudo apt-get install -y libjpeg62-turbo
+            fi
+
+            # Some images only provide libjpeg.so.62. Provide a compatibility symlink
+            # for qemu binaries linked against libjpeg.so.8.
+            if ! ldconfig -p | grep -q 'libjpeg\.so\.8'; then
+              jpeg_lib="$(ldconfig -p | awk '/libjpeg\.so/{print $NF; exit}')"
+              if [ -n "$jpeg_lib" ]; then
+                sudo ln -sf "$jpeg_lib" "$(dirname "$jpeg_lib")/libjpeg.so.8"
+                sudo ldconfig
+              fi
+            fi
           fi
           go mod download