fix(securitycenter): Update list findings to use the new Filter implementation (#4332)

Co-authored-by: Angel Caamal <acaamalcanul@google.com>
Co-authored-by: Jennifer Davis <sigje@google.com>

Author: 3 people

security-center/snippets/system-test/v1/findings.test.js

@@ -163,9 +163,7 @@ describe('Client with SourcesAndFindings', async () => {
     const output = exec(`node v1/listFindingsAtTime.js ${data.sourceName}`);
     // Nothing was created for the source more then a few minutes ago, so
     // days ago should return nothing.
-    //commented below assert and added new assert as source is created in before block
-    // assert.equal(output, '');
-    assert.include(output, data.sourceName);
+    assert.equal(output, '');
   });
 
   it('client can add security marks to finding', () => {

security-center/snippets/v1/listFindingsAtTime.js

@@ -37,14 +37,8 @@ function main(sourceName = 'FULL RESOURCE PATH TO PARENT SOURCE') {
 
   async function listFindingsAtTime() {
     const [response] = await client.listFindings({
-      // List findings across all sources.
       parent: sourceName,
-      //commented readTime as it is not supported, refer below link
-      //https://cloud.google.com/security-command-center/docs/release-notes#April_15_2024
-      // readTime: {
-      //   seconds: Math.floor(fiveDaysAgo.getTime() / 1000),
-      //   nanos: (fiveDaysAgo.getTime() % 1000) * 1e6,
-      // },
+      filter: `event_time < "${fiveDaysAgo.toISOString()}"`,
     });
     let count = 0;
     Array.from(response).forEach(result =>