This helps to clean the code a bit. Also, it makes
the rows to look consistent with other rows with
radio buttons, such as the ones from the
Multitasking and Keyboard panels
Doing this, the power profiles rows will look consistent
with other rows, such as the "Dynamic workspaces" and
"Fixed number of workspaces" from the Multitasking panel.
This also cleans the code a bit.
They were originally included was to educate users about what the icons
mean, for when they appeared in the top bar. However, since we no
longer plan on showing the status icon in the top bar, it's not so
important that people learn the meaning of the icons.
See https://gitlab.gnome.org/GNOME/gnome-control-center/-/issues/1421
