* Chore: Removes strict null checks in ReducerTester

* Chore: Fixes strict null errors in ConfigureStore

* Chore: Fixes strict null errors in reducer tests

* Chore: Fixes strict null errors in reducers tests

* Chore: Fixes strict null errors in reducers tests

* Chore: Fixes strict null errors in toggleLogActionsMiddleware

* Chore: Fixes strict null errors in navModelReducer

* Core: Fixes strict null errors in public/app/features/admin/state

* Chore: Fixes strict null errors in public/app/features/dashboard/state/reducers.test.ts

* Chore: Fixes strict null errors in public/app/features/explore/state/reducers.test.ts

* Chore: Fixes strict null errors in public/app/features/datasources/state/reducers.test.ts

* Chore: Fixes strict null errors in public/e2e-test/scenarios/templating/templatevariables-crud.test.ts

* Chore: Fixes strict null errors in public/app/features/dashboard/containers/DashboardPage.test.tsx