Use exponential-backoff for cache restore/save

analysis/packages/setup-ocaml/src/cache.ts

@@ -0,0 +1,57 @@
+async function restoreCache(
+  key: string,
+  restoreKeys: string[],
+  paths: string[],
+  options?: DownloadOptions,
+) {
+  if (!cache.isFeatureAvailable()) {
+    core.info("Actions cache service feature is unavailable");
+    return;
+  }
+  try {
+    const cacheKey = await cache.restoreCache(paths, key, restoreKeys, options);
+    if (cacheKey) {
+      core.info(`Cache restored from key: ${cacheKey}`);
+    } else {
+      core.info(
+        `Cache is not found for input keys: ${[key, ...restoreKeys].join(", ")}`,
+      );
+    }
+    return cacheKey;
+  } catch (error) {
+    if (error instanceof Error) {
+      core.info(`Cache restore error: ${error.message}`);
+    } else if (error instanceof AggregateError) {
+      core.info(
+        `Cache restore network error: ${error.code || "unknown error"}`,
+      );
+    } else {
+      core.info(`Cache restore unknown error: ${String(error)}`);
+    }
+    core.notice(
+      "An internal error has occurred in cache backend. Please check https://www.githubstatus.com for any ongoing issue in actions.",
+    );
+    return;
+  }
+}
+
+async function saveCache(key: string, paths: string[]) {
+  if (!cache.isFeatureAvailable()) {
+    core.info("Actions cache service feature is unavailable");
+    return;
+  }
+  try {
+    await cache.saveCache(paths, key);
+  } catch (error) {
+    if (error instanceof Error) {
+      core.info(`Cache save error: ${error.message}`);
+    } else if (error instanceof AggregateError) {
+      core.info(`Cache save network error: ${error.code || "unknown error"}`);
+    } else {
+      core.info(`Cache save unknown error: ${String(error)}`);
+    }
+    core.notice(
+      "An internal error has occurred in cache backend. Please check https://www.githubstatus.com for any ongoing issue in actions.",
+    );
+  }
+}