feat(core): add get available sso connectors endpoint

[simeng-li]

Summary

Add get available SSO connectors endpoint. Retrieve available SSO connectorIds for a given email.

Testing

integration tests added

Checklist

• [ ] .changeset
• [ ] unit tests
• [x] integration tests
• [ ] necessary TSDoc comments

[github-actions[bot]]

COMPARE TO master

Total Size Diff :chart_with_upwards_trend: +2.5 KB

Diff by File

|Name|Diff| |---|---| |packages/core/src/routes/experience/classes/validators/sign-in-experience-validator.ts|:chart_with_upwards_trend: +118 Bytes| |packages/core/src/routes/experience/verification-routes/enterprise-sso-verification.ts|:chart_with_upwards_trend: +774 Bytes| |packages/integration-tests/src/client/experience/index.ts|:chart_with_upwards_trend: +280 Bytes| |packages/integration-tests/src/tests/api/experience-api/verifications/enterprise-sso-verification.test.ts|:chart_with_upwards_trend: +1.36 KB|