ci: update actions/upload-artifact in GHA workflows to v6

Author: striezel

.github/workflows/alpine.yml

@@ -46,7 +46,7 @@ jobs:
           mv artifacts sha256_$VERSION
           tar czf sha256_${VERSION}_linux-amd64-generic.tar.gz sha256_$VERSION
       - name: Upload artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: sha256_linux-amd64-generic
           path: |

.github/workflows/alpine_arm.yml

@@ -69,7 +69,7 @@ jobs:
           mv artifacts sha256_$VERSION
           tar czf sha256_${VERSION}_linux-arm64-generic.tar.gz sha256_$VERSION
       - name: Upload artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: sha256_linux-arm64-generic
           path: |

.github/workflows/msys2.yml

@@ -66,7 +66,7 @@ jobs:
           mv artifacts sha256_$VERSION
           '/c/Program Files/7-Zip/7z.exe' a -r sha256_${VERSION}_win64.zip sha256_$VERSION
       - name: Upload artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: sha256_win64
           if-no-files-found: error