Use zstd instead of gzip if available

Add zstd to cache versioning

src/contracts.d.ts

@@ -1,3 +1,5 @@
+import { CompressionMethod } from "./constants";
+
 export interface ArtifactCacheEntry {
     cacheKey?: string;
     scope?: string;
@@ -17,3 +19,7 @@ export interface ReserveCacheRequest {
 export interface ReserveCacheResponse {
     cacheId: number;
 }
+
+export interface CacheOptions {
+    compressionMethod?: CompressionMethod;
+}