Adjust desktop file exec entries for targz package

# Please enter the commit message for your changes. Lines starting
# with '#' will be ignored, and an empty message aborts the commit.
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# Date:      Wed Apr 30 22:34:47 2025 +0200
#
# On branch release-0.49.0
# Changes to be committed:
#	modified:   CMakeLists.txt
#
