cache class for tool caching with gha

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

src/util.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import crypto from 'crypto';
 import fs from 'fs';
 import * as core from '@actions/core';
 import * as io from '@actions/io';
@@ -139,4 +140,8 @@ export class Util {
   public static sleep(seconds: number) {
     return new Promise(resolve => setTimeout(resolve, seconds * 1000));
   }
+
+  public static hash(input: string): string {
+    return crypto.createHash('sha256').update(input).digest('hex');
+  }
 }