Check that the Rust build script stays in sync with CMake configuration

To avoid a `cmake` dependency, the Rust bindings (`ittapi-rs`) use direct `cc` commands in its `build.rs` script to build the `ittnotify` library. These `cc` commands could eventually get out of sync with the `CMakeLists.txt` configuration. To avoid this, we could add a CI step that builds the C library using `cmake`, builds the C library using the `build.rs` script, hash both libraries, and check that the results are the same. This depends on #17 being implemented.