[Analysis Plugin] Add Found flag to GetApplicationSharedObject() to distinguish NotFound

[t-kikuc]

What this PR does:

as title

Why we need it:

To distinguish

• when the result does not exist yet
• when failed to get

https://github.com/pipe-cd/pipecd/blob/master/pkg/app/piped/apistore/analysisresultstore/store.go#L56-L71

Which issue(s) this PR fixes:

Part of #6068

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]

Codecov Report

❌ Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 28.67%. Comparing base (45a82f7) to head (0ed4509).
⚠️ Report is 6 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/plugin/sdk/client.go	0.00%	6 Missing ⚠️
pkg/app/pipedv1/cmd/piped/grpcapi/plugin_api.go	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6157      +/-   ##
==========================================
- Coverage   28.68%   28.67%   -0.01%     
==========================================
  Files         534      534              
  Lines       57328    57334       +6     
==========================================
  Hits        16442    16442              
- Misses      39608    39614       +6     
  Partials     1278     1278              

Flag	Coverage Δ
.	23.28% <0.00%> (-0.01%)	⬇️
.-pkg-app-pipedv1-plugin-analysis	62.85% <ø> (ø)
.-pkg-app-pipedv1-plugin-kubernetes	62.30% <ø> (ø)
.-pkg-app-pipedv1-plugin-kubernetes_multicluster	67.48% <ø> (ø)
.-pkg-app-pipedv1-plugin-scriptrun	54.83% <ø> (ø)
.-pkg-app-pipedv1-plugin-terraform	38.31% <ø> (ø)
.-pkg-app-pipedv1-plugin-wait	35.51% <ø> (ø)
.-pkg-app-pipedv1-plugin-waitapproval	68.62% <ø> (ø)
.-pkg-plugin-sdk	50.90% <0.00%> (-0.08%)	⬇️
.-tool-actions-gh-release	19.23% <ø> (ø)
.-tool-actions-plan-preview	25.30% <ø> (ø)
.-tool-codegen-protoc-gen-auth	0.00% <ø> (ø)

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[khanhtc1202]

Got the point, LGTM 🙆‍♂️

[Warashi]

LGTM