Revert "add -F and -X to default $LESS environment variable (#6611)"
Revert "add -F and -X to default $LESS environment variable (#6611)"

This reverts commit 9544316ef95c2aa1e75101a7dce545b4604b3ca6.

This setting broke mouse / touchpad scroll on programs using `less` output
due to it not using the alternate screen buffer.

Fixes #7025

tekniklr/oh-my-zsh,tekniklr/oh-my-zsh