Update actions/cache version to v4 in workflow files

Author: zfergus

.github/workflows/continuous.yml

@@ -66,7 +66,7 @@ jobs:
 
       - name: Cache Build
         id: cache-build
-        uses: actions/cache@v4.0.2
+        uses: actions/cache@v4
         with:
           path: ${{ env.CACHE_PATH }}
           key: ${{ runner.os }}-${{ matrix.config }}-cache

.github/workflows/coverage.yml

@@ -35,7 +35,7 @@ jobs:
 
       - name: Cache Build
         id: cache-build
-        uses: actions/cache@v4.0.2
+        uses: actions/cache@v4
         with:
           path: ${{ env.CACHE_PATH }}
           key: coverage-cache

.github/workflows/cuda.yml

@@ -36,7 +36,7 @@ jobs:
         run: |
           sudo apt-get install ccache
           echo 'CACHE_PATH=~/.cache/ccache' >> "$GITHUB_ENV"
-      
+
       - name: cuda-toolkit
         uses: Jimver/[email protected]
         with:
@@ -49,7 +49,7 @@ jobs:
 
       - name: Cache Build
         id: cache-build
-        uses: actions/cache@v4.0.2
+        uses: actions/cache@v4
         with:
           path: ${{ env.CACHE_PATH }}
           key: ${{ runner.os }}-${{ matrix.config }}-cache

.github/workflows/docs.yml

@@ -31,7 +31,7 @@ jobs:
 
       - name: Cache Build
         id: cache-build
-        uses: actions/cache@v4.0.2
+        uses: actions/cache@v4
         with:
           path: ${{ env.CACHE_PATH }}
           key: docs-cache

.github/workflows/python.yml

@@ -62,7 +62,7 @@ jobs:
 
       - name: Cache Build
         id: cache-build
-        uses: actions/cache@v4.0.2
+        uses: actions/cache@v4
         with:
           path: ${{ env.CACHE_PATH }}
           key: ${{ runner.os }}-Python${{ matrix.python-version }}-cache