fix(JXL): Correctly set Quality for JPEG XL (#4933)

Distance in JPEG XL isn't linear, causing previous quality settings to
scale between lossless and visually lossless, instead of lossless and
the lowest quality.

Quality | libjxl Distance | Old OIIO Distance
|--------|------|------|
| 99 | 0.19 | 0.01 |
| 90  | 1.00 | 0.01 |
| 80  | 1.90 | 0.01 |
| 70  | 2.80 | 0.01 |
| 60  | 3.70 | 0.02 |
| 50  | 4.60 | 0.02 |
| 40  | 5.50 | 0.03 |
| 30  | 6.40 | 0.03 |
| 20  | 8.13 | 0.05 |
| 10  | 13.27 | 0.10 |
| 1   | 24.24 | 1.00 |
| 0   | 25.00 | Error |

Thankfully libjxl has a built in function to convert Quality to
Distance, so I've swapped it in.
Unable to test it myself, but it's a simple fix that I ran by another
libjxl dev too.

---------

Signed-off-by: Jonathan Brown <[email protected]>

Author: jonnyawsom3

src/jpegxl.imageio/jxloutput.cpp

@@ -228,9 +228,9 @@ JxlOutput::open(const std::string& name, const ImageSpec& newspec,
                 lossless = true;
             } else {
                 m_basic_info.uses_original_profile = JXL_FALSE;
-                JxlEncoderSetFrameDistance(
-                    m_frame_settings,
-                    1.0f / static_cast<float>(compqual.second));
+                const float distance = JxlEncoderDistanceFromQuality(
+                    compqual.second);
+                JxlEncoderSetFrameDistance(m_frame_settings, distance);
                 JxlEncoderSetFrameLossless(m_frame_settings, JXL_FALSE);
             }
         } else {  // default to lossless