Update pillow requirement from <10.2,>=9.5 to >=9.5,<10.4

Updates the requirements on [pillow](https://github.com/python-pillow/Pillow) to permit the latest version.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/main/CHANGES.rst)
- [Commits](python-pillow/Pillow@9.5.0...10.3.0)

---
updated-dependencies:
- dependency-name: pillow
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -23,7 +23,7 @@ dependencies = [
     'midi_const~=0.1.0',
     'mido~=1.3.0', # FIXME: currently using custom 1.2.11a1 with EOX, running status and delta time support
     'python-rtmidi~=1.5.5', # While it's mido's default backend, we explicitly require it for some features.
-    'Pillow>=9.5,<10.2',
+    'Pillow>=9.5,<10.4',
 ]
 license = { file = 'LICENSE' }
 authors = [