Flip logic for determining if $section variable is set.

[braders]

Overview

Previously empty() function calls were added in order to provide PHP8 compatiability,
however, the logic commited was back-to-front.

This broke the ability to display pie and bar charts for those reports which support them.

Before

Attempting to display a bar or pie chart for a report failed, with the following error message in the browser devconsole:

Uncaught ReferenceError: createChart is not defined

After

Pie and bar charts should work again.

Technical Details

This was broken in 0c1caf1.

TBH I'm not sure what the check on $section is doing, or if it's even needed. Maybe someone smarter than me will know? Seemed safest to just leave it be for now though.

[civibot]

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[demeritcowboy]

Thanks that makes sense and I can reproduce.