Editing install_software_using_appimage.md

[sspencerwire]

• fix some spacing and line-feed issues
• replace passive voice with active where necessary
• replace conjunctions with words
• some minor sentence simplification

Author checklist (Completed by original Author)

• Good fit for the Rocky Linux project? Title and Author Metatags inserted ?
• If applicable, steps and instructions have been tested to work
• Initial self-review to fix basic typos and grammar completed

Rocky Documentation checklist (Completed by Rocky team)

• 1st Pass (Document is good fit for project and author checklist completed)
• 2nd Pass (Technical Review - check for technical correctness)
• 3rd Pass (Detailed Editorial Review and Peer Review)
• Final approval (Final Review)

[github-actions]

Test results for 6dda75b:

Number of broken URLs: 2

URL,RESULT,FILENAME
 http://developer.download.nvidia/compute/cuda/repos/rhel9/$,failed,desktop/display/installing_nvidia_gpu_drivers.md
 https://azuremarketplace.microsoft.com/en-us/marketplace/apps/resf.rockylinux-aarch64,failed,guides/cloud/migration-to-new-azure-images.md