chore(deps): 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] <[email protected]>

.github/workflows/check.yml

@@ -31,7 +31,7 @@ jobs:
     
     - name: Archive failed test output
       if: failure()
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: test-diff-files
         path: build/test*/*.diff

.github/workflows/doc.yml

@@ -29,7 +29,7 @@ jobs:
       run: |
         l3build doc -q
 
-    - uses: actions/upload-artifact@v3
+    - uses: actions/upload-artifact@v4
       with:
         name: pgfmanual
         path: build/doc/pgfmanual.pdf

.github/workflows/main.yml

@@ -51,7 +51,7 @@ jobs:
       run: |
         l3build ctan
 
-    - uses: actions/upload-artifact@v3
+    - uses: actions/upload-artifact@v4
       with:
         name: pgfmanual
         path: build/doc/pgfmanual.pdf