Update Teacher Training API to return `selectable_school` #10578

Job	Run time
Build	3m 37s
Lint (rubocop)	1m 45s
Test (unit_models)	3m 21s
Lint (erblint)	1m 14s
Test (unit_services)	1m 38s
Lint (dfe_analytics)	1m 5s
Test (unit_forms)	1m 25s
Lint (yarn_lint_and_test)	1m 1s
Test (unit_components)	1m 12s
Test (unit_other)	2m 11s
Test (integration_auth)	1m 11s
Test (integration_find)	1m 24s
Test (integration_publish)	2m 50s
Test (integration_support)	1m 19s
Test (integration_other)	1m 7s
Deployment To Review v2	4m 42s
Parallel deployment before production v2	0s
Production deployment v2	0s
Sandbox deployment v2	0s
	31m 2s

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