Bump julia-actions/cache to v3, remove cache-save workaround

julia-actions/cache@v3 saves the cache on failure/cancellation natively,
so the explicit actions/cache/save fallback step is no longer needed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: hexaeder

.github/workflows/CI.yml

@@ -29,23 +29,13 @@ jobs:
         with:
           version: ${{ matrix.version }}
           arch: ${{ matrix.arch }}
-      - name: Load Julia packages from cache
-        id: julia-cache
-        uses: julia-actions/cache@v3
+      - uses: julia-actions/cache@v3
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v5
         with:
           file: lcov.info
-      - name: Save Julia depot cache on cancel or failure
-        id: julia-cache-save
-        if: cancelled() || failure()
-        uses: actions/cache/save@v5
-        with:
-          path: |
-            ${{ steps.julia-cache.outputs.cache-paths }}
-          key: ${{ steps.julia-cache.outputs.cache-key }}
   docs:
     name: Documentation
     runs-on: ubuntu-latest
@@ -57,9 +47,7 @@ jobs:
       - uses: julia-actions/setup-julia@v2
         with:
           version: '1'
-      - name: Load Julia packages from cache
-        id: julia-cache
-        uses: julia-actions/cache@v3
+      - uses: julia-actions/cache@v3
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-docdeploy@v1
         env:
@@ -71,11 +59,3 @@ jobs:
             using NetworkLayout
             DocMeta.setdocmeta!(NetworkLayout, :DocTestSetup, :(using NetworkLayout); recursive=true)
             doctest(NetworkLayout)'
-      - name: Save Julia depot cache on cancel or failure
-        id: julia-cache-save
-        if: cancelled() || failure()
-        uses: actions/cache/save@v5
-        with:
-          path: |
-            ${{ steps.julia-cache.outputs.cache-paths }}
-          key: ${{ steps.julia-cache.outputs.cache-key }}