Bump actions/upload-artifact from 3 to 4

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 3 to 4.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v3...v4)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/biblatex.yml

@@ -30,7 +30,7 @@ jobs:
         run: |
           python .utils/biblatex_merger.py . tex/bibliography.bib
       - name: Upload biblatex file
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: Merged biblatex file
           path: tex/bibliography.bib

.github/workflows/latex.yml

@@ -28,7 +28,7 @@ jobs:
           texlive_version: 2023
           # args: -f
       - name: Upload PDF file
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: Compiled main PDF
           path: tex/main.pdf