[ENHANCEMENT] Replace #define constants with const variables in run_dynamics_fast

### Relation

The MATLAB mex function, [`run_dynamics_fast`](https://github.com/Airspace-Encounter-Models/em-core/blob/master/matlab/utilities-1stparty/runDynamicsFast/run_dynamics_fast.c) is used by multiple repositories, including `em-model-manned-bayes` to simulate aircraft trajectories with a 6DOF physics model. There are various `#define` statements that define constants.

### Description

Per the Google C++ Style Guide for [preprocessor macros](https://google.github.io/styleguide/cppguide.html#Preprocessor_Macros):
> Instead of using a macro to store a constant, use a `const` variable.

### Alternatives

Using `const` instead of `#define` is a good best practice and should be implemented.

### Additional

While the contributing guidelines does not define a style guide for C++, we currently recommend the [Google C++ Style Guide](https://google.github.io/styleguide/cppguide.html) for this issue.