tests: add retries and some delays to try to clear up some CI issues around quotas and timeouts (#1759)

Author: feywind

handwritten/bigtable/package.json

@@ -36,9 +36,9 @@
     "lint": "gts check",
     "prepare": "npm run compile-protos && npm run compile",
     "samples-test": "cd samples/ && npm link ../ && npm install && npm test && cd ../",
-    "snippet-test": "mocha samples/api-reference-doc-snippets/tests/*.js --timeout 600000",
+    "snippet-test": "mocha samples/api-reference-doc-snippets/tests/*.js --timeout 600000 --retries 3",
     "presystem-test": "npm run compile",
-    "system-test": "mocha build/system-test --timeout 600000",
+    "system-test": "mocha build/system-test --timeout 600000 --retries 3",
     "pretest": "npm run compile",
     "test": "c8 mocha build/test",
     "test:snap": "SNAPSHOT_UPDATE=1 npm test",

handwritten/bigtable/system-test/bigtable.ts

@@ -1904,6 +1904,11 @@ describe('Bigtable', () => {
       nanos: 0,
     };
 
+    beforeEach(async () => {
+      // This is not ideal, but we are running into quota issues for admin API access.
+      await new Promise(r => setTimeout(r, 60 * 1000));
+    });
+
     before(async () => {
       const [backupOpSSD] = await tableAdmin.createBackup({
         parent: replaceProjectIdToken(