Chore/CI: use fs cache to save bandwidth

Build/download-publicsuffixlist.ts

@@ -0,0 +1,10 @@
+import { fsCache } from './lib/cache-filesystem';
+import { defaultRequestInit, fetchWithRetry } from './lib/fetch-retry';
+import { createMemoizedPromise } from './lib/memo-promise';
+import { traceAsync } from './lib/trace-runner';
+
+export const getPublicSuffixListTextPromise = createMemoizedPromise(() => traceAsync('obtain public_suffix_list', () => fsCache.apply(
+  'public_suffix_list.dat',
+  () => fetchWithRetry('https://publicsuffix.org/list/public_suffix_list.dat', defaultRequestInit).then(r => r.text()),
+  { ttl: 24 * 60 * 60 * 1000 }
+)));