Bump actions/upload-artifact from 5 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v5...v6)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/main.yml

@@ -63,7 +63,7 @@ jobs:
         run: |
           sh pd-lib-builder-iem-ci/localdeps/localdeps.linux.sh pkglibdir/asdf/asdf~.pd_linux
       - name: Upload Pd external
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: Linux Pd external
           path: pure-data/pkglibdir/asdf/*
@@ -122,7 +122,7 @@ jobs:
         run: |
           sh pd-lib-builder-iem-ci/localdeps/localdeps.macos.sh pkglibdir/asdf/asdf~.pd_darwin
       - name: Upload Pd external
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: macOS Pd external
           path: pure-data/pkglibdir/asdf/*
@@ -174,7 +174,7 @@ jobs:
         run: |
           sh pd-lib-builder-iem-ci/localdeps/localdeps.win.sh pkglibdir/asdf/asdf~.dll
       - name: Upload Pd external
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: Windows Pd external
           path: pure-data/pkglibdir/asdf/*
@@ -257,7 +257,7 @@ jobs:
         run: |
           deken package -v $(git describe --tags --always) --objects pure-data/objects.txt asdf
       - name: Upload deken package
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: Deken package
           path: "*.dek*"