When using SAPI from an external project via CMake, the small zlib patch
cannot be found during the config phase.
This change also fixes an oversight in that the tests depend on some of
the example code.
Regardless embedding code should set `SAPI_ENABLE_EXAMPLES` to `OFF`.
Disabling tests by setting `SAPI_ENABLE_TESTS` to `OFF` stays optional.
PiperOrigin-RevId: 311290454
Change-Id: Ibe105895859b793b20f47c89b1a9e11cbfef2e2f
Similar to what the Bazel build does, this change adds zlib as an additional
dependency when `SAPI_ENABLE_EXAMPLES` is set to `ON`.
PiperOrigin-RevId: 309203959
Change-Id: I201a9e6415789afb1e058bc48cebbc0fc0004fe9