Refactor deployment config file form

[cakecatz]

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Does this PR introduce a user-facing change?:

NONE

[pipecd-bot]

Code coverage for golang is 32.96%. This pull request does not change code coverage.

[pipecd-bot]

Code coverage for javascript is 83.78%. This pull request decreases coverage by -0.39%.

File	Base	Head	Diff
src/components/application-detail.tsx	100.00%	95.92%	-4.08%
src/modules/applications-live-state.ts	65.22%	66.67%	+1.45%
src/modules/applications.ts	89.13%	85.71%	-3.42%
src/pages/applications/detail.tsx	100.00%	84.62%	-15.38%

[nghialv]

/approve

[pipecd-bot]

This pull request is APPROVED by nghialv.

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