build(deps): bump rapidocr-onnxruntime from 1.3.24 to 1.4.4 in /backend

Bumps [rapidocr-onnxruntime](https://github.com/RapidAI/RapidOCR) from 1.3.24 to 1.4.4.
- [Release notes](https://github.com/RapidAI/RapidOCR/releases)
- [Commits](https://github.com/RapidAI/RapidOCR/compare/v1.3.24...v1.4.4)

---
updated-dependencies:
- dependency-name: rapidocr-onnxruntime
  dependency-version: 1.4.4
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

backend/requirements.txt

@@ -81,7 +81,7 @@ azure-ai-documentintelligence==1.0.0
 
 pillow==11.1.0
 opencv-python-headless==4.11.0.86
-rapidocr-onnxruntime==1.3.24
+rapidocr-onnxruntime==1.4.4
 rank-bm25==0.2.2
 
 onnxruntime==1.20.1