extensions: image-output-abl: set rootfs image larger for kde

[amazingfate]

Description

KDE image with all appgroups is larger than 9216M, so increase the abl image size to 9728M

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Please also note any relevant details for your test configuration.

• ./compile.sh BOARD=xiaomi-elish BRANCH=current GITHUB_MIRROR=ghproxy KERNEL_GIT=shallow DEB_COMPRESS=xz RELEASE=noble BUILD_DESKTOP=yes BUILD_MINIMAL=no KERNEL_CONFIGURE=no DESKTOP_APPGROUPS_SELECTED="chat,desktop_tools,editors,email,internet,languages,multimedia,office,programming,remote_desktop" DESKTOP_ENVIRONMENT=kde-neon DESKTOP_ENVIRONMENT_CONFIG_NAME=config_base EXPERT=yes

Checklist:

Please delete options that are not relevant.

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules