Restrict CFE_EVS_SendEventWithAppID to core use only

[skliper]

Is your feature request related to a problem? Please describe.
Similar to #1388 which would be a bigger change, but at minimum should remove this from the public API so libs don't start using it.

Describe the solution you'd like
Move to internal/private. Also need to confirm requirements match up.

Describe alternatives you've considered
#1388 - probably should be removed all together, but that's a bigger issue

Additional context
Code review

Requester Info
Jacob Hageman - NASA/GSFC

[skliper]

CCB: 2021-04-21 - decided against restricting. There is a valid use case, and filtering/reporting could be updated to make this more obvious (There's EID context and calling context that is helpful).