Will a graceful reload of Apache configuration require the SSL Cert password?
No. SSL certificates are only reloaded on a full restart, not a graceful one.
This means you won't need to re-enter the password on a reload/graceful, and also means that changes to the certificates/new certificates/etc require a full restart to take effect.
Because there is a bit of confusion about full restart and graceful restart I must say that
Fully restarts the server but that is not gracefully done. This means that current connections are aborted.
What you want to achieve can be done gracefully with:
Both methods reload the certificates.
Which does a full apache restart, but the active connections are not aborted. It does not accept new connections until the current ones finish processing and restarts after that.
In conclusion, both
graceful do a full apache restart, but graceful does not abort connections, waits for them to be closed, then it restarts.