Code review comment for ~mitchdz/ubuntu/+source/apache2:noble-add-ubuntu-logo

Thanks Sergio. I applied most suggestions except `set -o lastpipe` since I am using sh instead of bash in this script.

local autopkgtest result on amd64:

$ autopkgtest -U -s -o "dep8-apache2" --test-name=check-ubuntu-branding ../apache2_2.4.57-2ubuntu3\~noble3.dsc -- qemu "/var/lib/adt-images/autopkgtest-noble-amd64.img"
....
autopkgtest [23:36:22]: test check-ubuntu-branding: [-----------------------
+ ubuntu_logo_path=icons/ubuntu-logo.png
+ grep -qF icons/ubuntu-logo.png
+ curl -s -k http://localhost
+ tr -d [:space:]
+ cut -d -f 2-
+ grep Content-Type
+ curl -s -I http://localhost/icons/ubuntu-logo.png
+ content_type=image/png
+ expected=image/png
+ [ image/png != image/png ]
autopkgtest [23:36:23]: test check-ubuntu-branding: -----------------------]
check-ubuntu-branding PASS
autopkgtest [23:36:23]: test check-ubuntu-branding: - - - - - - - - - - results - - - - - - - - - -
autopkgtest [23:36:24]: @@@@@@@@@@@@@@@@@@@@ summary
check-ubuntu-branding PASS