Adding status and end date to SubscriptionPlan

Added a subscription plan status and expiration date to
SusbcriptionPlan.

Flag: com.android.internal.telephony.flags.subscription_plan_allow_status_and_end_date

Test: atest FrameworksTelephonyTests:SubscriptionPlanTest
Test: atest CtsTelephonyTestCases:SubscriptionManagerTest
Bug: 357272015
Change-Id: Ia6d11cb54befdf92dbabb6abe84fd59d18e1c6b3