Zod tests still use deprecated functions

[ThanGerlek]

Description

Several test files in v4/classic still use deprecated or legacy forms of various functions (z.string().date() instead of z.iso.date(), z.number().safe() instead of z.int(), etc.).

Some of these are unrelated test cases that happen to use deprecated forms (like z.string().email() in a template literal test), which simply need to be migrated. Others are relevant functionality tests (like z.string.email() in an email validation test)--the tests are currently somewhat inconsistent about using current or deprecated versions, and this should be standardized.

Decisions to make

When testing functionality that has both current and deprecated versions, should we test just the new, just the old, or both?

[colinhacks]

In general the old APIs just delegate to the new ones. I left in several deprecated APIs because that way it tests both. People can do whichever they want. Not worth the bandwidth at the moment.