chore: Fix sorting issue in PhotoGridByYear component

This commit fixes a sorting issue in the PhotoGridByYear component. The index difference calculation in the `PhotoGridByYear` component was incorrect, causing the sorting to be reversed. This commit corrects the calculation to ensure the correct sorting order is maintained.

```

src/components/Body/PhotoGridByYear.jsx

@@ -26,7 +26,7 @@ const PhotoGridByYear = ({ photos, handleClick }) => {
         const yearA = a[0];
         const yearB = b[0];
         const yearIndex = (targetYear) => places.findIndex(({ year }) => year === targetYear);
-        const indexDiff = yearIndex(yearA) - yearIndex(yearB);
+        const indexDiff = yearIndex(yearB) - yearIndex(yearA);
         if (indexDiff !== 0) {
             return indexDiff;
         }