Update actions/cache to v4.

(cherry picked from commit 1957ba0)

Author: ting-yuan

.github/workflows/auto-merge.yml

@@ -50,15 +50,15 @@ jobs:
 
       # Build cache
       - name: Cache Gradle Cache
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.gradle/caches
           key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}-${{ hashFiles('**/gradle.properties') }}
           # An ordered list of keys to use for restoring the cache if no cache hit occurred for key
           restore-keys: |
             ${{ runner.os }}-gradle-
       - name: Cache gradle wrapper
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.gradle/wrapper
           key: ${{ runner.os }}-gradle-wrapper-${{ hashFiles('gradle/wrapper/gradle-wrapper.properties') }}

.github/workflows/main.yml

@@ -46,15 +46,15 @@ jobs:
 
     # Build cache
     - name: Cache Gradle Cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.gradle/caches
         key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}-${{ hashFiles('**/gradle.properties') }}
         # An ordered list of keys to use for restoring the cache if no cache hit occurred for key
         restore-keys: |
           ${{ runner.os }}-gradle-
     - name: Cache gradle wrapper
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.gradle/wrapper
         key: ${{ runner.os }}-gradle-wrapper-${{ hashFiles('gradle/wrapper/gradle-wrapper.properties') }}

.github/workflows/release.yml

@@ -25,15 +25,15 @@ jobs:
 
     # Build cache
     - name: Cache Gradle Cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.gradle/caches
         key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}-${{ hashFiles('**/gradle.properties') }}
         # An ordered list of keys to use for restoring the cache if no cache hit occurred for key
         restore-keys: |
           ${{ runner.os }}-gradle-
     - name: Cache gradle wrapper
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.gradle/wrapper
         key: ${{ runner.os }}-gradle-wrapper-${{ hashFiles('gradle/wrapper/gradle-wrapper.properties') }}