[Lambda] Fix unexpected diff of Plan Preview

[t-kikuc]

The same issue as #5306 (ECS). See it for details.

What this PR does:

• Clone manifests in DriftDetection not to modify the original ones in AppManifestsCache.

Why we need it:

PlanPreview for Lambda has the same issue as #5306.

Which issue(s) this PR fixes:

N/A

Does this PR introduce a user-facing change?:

• How are users affected by this change:
• Is this breaking change:
• How to migrate (if breaking change):

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 69.56522% with 7 lines in your changes missing coverage. Please review.

Project coverage is 25.25%. Comparing base (ad3c877) to head (f528641). Report is 9 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/app/piped/driftdetector/lambda/detector.go	69.56%	7 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #5308 +/- ## ========================================== + Coverage 25.14% 25.25% +0.10% ========================================== Files 449 444 -5 Lines 47642 47493 -149 ========================================== + Hits 11980 11994 +14 + Misses 34717 34558 -159 + Partials 945 941 -4 ```

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