Update DeterminateSystems/magic-nix-cache-action action to v15 (#1014)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/nix.yaml

@@ -27,7 +27,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - run: nix flake check -L
 
@@ -47,7 +47,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - name: Main project tests
         run: gradle test --no-daemon
@@ -74,7 +74,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - run: bazelisk build //... ${{ matrix.javac_option }}
         working-directory: ${{ matrix.directory }}
@@ -92,7 +92,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - run: gradle :scip-java:installDist --no-daemon
       - run: printf 'SCIP_JAVA_CLI=%s\n' "$PWD/scip-java/build/install/scip-java/bin/scip-java" >> "$GITHUB_ENV"
@@ -117,7 +117,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - name: Regenerate snapshots
         run: gradle :scip-snapshots:saveSnapshots --no-daemon
@@ -143,7 +143,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - run: |
           gradle --no-daemon :scip-java:installDist publishToMavenLocal

.github/workflows/release-cli.yaml

@@ -23,7 +23,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - name: Build standalone launcher
         env:

.github/workflows/release-maven.yaml

@@ -14,7 +14,7 @@ jobs:
       - uses: DeterminateSystems/nix-installer-action@v22
         with:
           summarize: false
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
       - name: Publish snapshot ${{ github.ref }}
         if: ${{ !startsWith(github.ref, 'refs/tags/') }}
         run: nix develop --command gradle --no-daemon publishToMavenCentral

.github/workflows/repos.yaml

@@ -32,7 +32,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - name: Build distribution
         run: gradle :scip-java:installDist --no-daemon
@@ -145,7 +145,7 @@ jobs:
         with:
           summarize: false
 
-      - uses: DeterminateSystems/magic-nix-cache-action@v14
+      - uses: DeterminateSystems/magic-nix-cache-action@v15
 
       - uses: actions/download-artifact@v8
         with: