Fix shellcheck issue SC2086 (quotes)

SC2086: Double quote to prevent globbing and word splitting.

Also remove it from the exclude list in the CI config file.

debian/salsa-ci.yml

@@ -26,7 +26,7 @@ shellcheck:
   script:
     - apt-get update && apt-get upgrade -y
     - apt-get install -y shellcheck
-    - shellcheck -e SC1090,SC1091,SC2086 -s dash $(find rootfs/etc/initramfs-tools -type f -executable  | xargs grep -l '^#!/bin/sh')
+    - shellcheck -e SC1090,SC1091 -s dash $(find rootfs/etc/initramfs-tools -type f -executable  | xargs grep -l '^#!/bin/sh')
 
 build yamls:
   stage: build