fix(integ-runner): always resynth on deploy (#20508)

We were trying to save time by re-using a previously synthed cloud
assembly if it existed, but we should not be doing this. When we perform
the deployment we could be using new settings (or context) that needs to
be applied to the synth.


----

### All Submissions:

* [ ] Have you followed the guidelines in our [Contributing guide?](https://github.com/aws/aws-cdk/blob/master/CONTRIBUTING.md)

### Adding new Unconventional Dependencies:

* [ ] This PR adds new unconventional dependencies following the process described [here](https://github.com/aws/aws-cdk/blob/master/CONTRIBUTING.md/#adding-new-unconventional-dependencies)

### New Features

* [ ] Have you added the new feature to an [integration test](https://github.com/aws/aws-cdk/blob/master/INTEGRATION_TESTS.md)?
	* [ ] Did you use `yarn integ` to deploy the infrastructure and generate the snapshot (i.e. `yarn integ` without `--dry-run`)?

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/integ-runner/lib/runner/integ-test-runner.ts

@@ -259,7 +259,7 @@ export class IntegTestRunner extends IntegRunner {
         ...actualTestCase?.cdkCommandOptions?.deploy?.args,
         ...actualTestCase.assertionStack ? { outputsFile: path.join(this.cdkOutDir, 'assertion-results.json') } : undefined,
         context: this.getContext(actualTestCase?.cdkCommandOptions?.deploy?.args?.context),
-        app: this.hasTmpActualSnapshot() ? this.cdkOutDir : this.cdkApp,
+        app: this.cdkApp,
       });
 
       if (actualTestCase.hooks?.postDeploy) {

packages/@aws-cdk/integ-runner/lib/runner/runner-base.ts

@@ -146,7 +146,7 @@ export abstract class IntegRunner {
       this.testName = testName;
     } else {
       const relativePath = path.relative(options.directory, parsed.dir);
-      this.testName = `${relativePath ? relativePath+'/' : ''}${parsed.name}`;
+      this.testName = `${relativePath ? relativePath + '/' : ''}${parsed.name}`;
     }
     this.snapshotDir = path.join(this.directory, `${testName}.integ.snapshot`);
     this.relativeSnapshotDir = `${testName}.integ.snapshot`;
@@ -210,10 +210,6 @@ export abstract class IntegRunner {
     return fs.existsSync(this.snapshotDir);
   }
 
-  public hasTmpActualSnapshot(): boolean {
-    return fs.existsSync(path.join(this.directory, this.cdkOutDir));
-  }
-
   /**
    * Load the integ manifest which contains information
    * on how to execute the tests
@@ -371,7 +367,7 @@ export abstract class IntegRunner {
   }
 
   protected getContext(additionalContext?: Record<string, any>): Record<string, any> {
-    const futureFlags: {[key: string]: any} = {};
+    const futureFlags: { [key: string]: any } = {};
     Object.entries(FUTURE_FLAGS)
       .filter(([k, _]) => !FUTURE_FLAGS_EXPIRED.includes(k))
       .forEach(([k, v]) => futureFlags[k] = v);

packages/@aws-cdk/integ-runner/test/runner/integ-test-runner.test.ts

@@ -78,7 +78,7 @@ describe('IntegTest runIntegTests', () => {
       stacks: ['test-stack'],
     });
     expect(deployMock).toHaveBeenCalledWith({
-      app: 'cdk-integ.out.test-with-snapshot',
+      app: 'node integ.test-with-snapshot.js',
       requireApproval: 'never',
       pathMetadata: false,
       assetMetadata: false,