Add parole terminations metric for PA

[macfarlandian]

Description of the change

This replaces the original parole success metric with the new "successful parole terminations" variation for Pennsylvania (necessary for data availability reasons, as seen in https://github.com/Recidiviz/recidiviz-data/pull/8155). Mostly this change is boilerplate and the new metric is a drop-in replacement, though it does require its own data transformation functions to handle the slightly different API response.

(Files are in staging, you can run the backend from this branch to test locally)

Type of change

• New feature (non-breaking change that adds functionality)

Related issues

Closes #452

Checklists

Development

These boxes should be checked by the submitter prior to merging:

• Manual testing against realistic data has been performed locally

Code review

These boxes should be checked by reviewers prior to merging:

• This pull request has a descriptive title and information useful to a reviewer
• This pull request has been moved out of a Draft state, has no "Work In Progress" label, and has assigned reviewers
• Potential security implications or infrastructural changes have been considered, if relevant

[coveralls]

Pull Request Test Coverage Report for Build 1027866502

• 3 of 10 (30.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.2%) to 84.946%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
spotlight-client/src/contentModels/createMetricMapping.ts	3	4	75.0%
spotlight-client/src/metricsApi/SupervisionSuccessRateDemographicsRecord.ts	0	2	0.0%
spotlight-client/src/metricsApi/SupervisionSuccessRateMonthlyRecord.ts	0	4	0.0%

Totals
Change from base Build 969619346:	-0.2%
Covered Lines:	1939
Relevant Lines:	2161

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💛 - Coveralls