ci: pin GitHub actions via SHA

Signed-off-by: Stefan Kraus <dev@stefankraus.org>

Author: Alicipy

action.yml

@@ -187,7 +187,7 @@ runs:
         echo "SETUP_OPT=${setup_opt}" >> $GITHUB_ENV
 
     - name: Cache Python packages
-      uses: actions/cache@v4
+      uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 #v4.3.0
       with:
         path: ${{ env.PIP_CACHE_PATH }}
         key: pip-${{ runner.os }}-${{ hashFiles(format('{0}/zephyr/scripts/requirements*.txt', inputs.base-path)) }}
@@ -202,7 +202,7 @@ runs:
 
     - name: Cache Zephyr SDK
       id: cache-toolchain
-      uses: actions/cache@v4
+      uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 #v4.3.0
       with:
         path: ${{ inputs.base-path }}/zephyr-sdk
         key: ${{ env.SDK_FILE }}-${{ github.event.repository.name }}-${{ inputs.toolchains }}
@@ -237,7 +237,7 @@ runs:
 
     - name: Cache ccache data
       if: inputs.enable-ccache == 'true' && runner.os != 'Windows'
-      uses: actions/cache@v4
+      uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 #v4.3.0
       with:
         path: ${{ env.CCACHE_DIR }}
         key: ccache-${{ inputs.ccache-cache-key }}-${{ env.CCACHE_TIMESTAMP }}