LibGfx: Fix bounds checking in `accumulate_even_odd_scanline()`

`edge_extent.max_x` is inclusive so it must be < `m_scanline.size()`.

Userland/Libraries/LibGfx/EdgeFlagPathRasterizer.cpp

@@ -310,7 +310,7 @@ auto EdgeFlagPathRasterizer<SamplesPerPixel>::accumulate_even_odd_scanline(EdgeE
 {
     SampleType sample = init;
     VERIFY(edge_extent.min_x >= 0);
-    VERIFY(edge_extent.max_x <= static_cast<int>(m_scanline.size()));
+    VERIFY(edge_extent.max_x < static_cast<int>(m_scanline.size()));
     for (int x = edge_extent.min_x; x <= edge_extent.max_x; x += 1) {
         sample ^= m_scanline.data()[x];
         sample_callback(x, sample);