Proposed schedule for JavaFX 23

[Kevin Rushforth]

Here is the proposed schedule for JavaFX 23.

RDP1: Jul 11, 2024 (aka “feature freeze”)
RDP2: Aug 1, 2024
Freeze: Aug 29, 2024
GA: Sep 17, 2024

We plan to fork a jfx23 stabilization branch at RDP1.

The start of RDP1, the start of RDP2, and the code freeze will be 16:00 
UTC on the respective dates.

Please let Johan or me know if you have any questions.

-- Kevin