746d38a6

By: Michael Lynch <git@mtlynch.io>

Simplify login_tokens_test.go by using concrete sqlite.Store type

Replace verbose inline interface declarations with sqlite.Store in setup
functions and table-driven test fields. The test already depends on
test_sqlite.New() which returns sqlite.Store, so the anonymous
interfaces added no value and repeated the InsertUser/InsertLoginToken
signatures four times.

Also reuse insertTestUser helper in TestConsumeLoginToken_AlreadyUsed
and TestReadUserByEmail, which previously inlined the same InsertUser
call.