Update version of actions/cache to use undepreacted version.

Author: taeold

.github/workflows/docs.yaml

@@ -15,7 +15,7 @@ jobs:
         with:
           node-version: "20"
       - name: Cache npm
-        uses: actions/cache@v1
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-docgen-${{ hashFiles('**/package-lock.json') }}