jfx23u open for JavaFX 23.0.1 backports

[Kevin Rushforth]

All,

The jfx23u repo [1] is now open for JavaFX 23.0.1 backports (the October 
2024 CPU release), with prior approval. The general criteria is that we 
want to backport fixes for regressions introduced in JavaFX 23, 
third-party library updates, and a limited number of other important bug 
fixes. In most cases we'd like to see the fix "bake" in the mainline for 
a while before being backported to jfx23u.

NOTE: Only those fixes that will NOT be backported to the jfx23 [2] 
stabilization branch are candidates for backporting to jfx23u. A 
backport intended for the JavaFX 23 code line will go into either the 
jfx23 branch or the jfx23u repo, not both.

We use a similar procedure for making the request and noting the 
approval as is used by the JDK updates releases -- by using JBS labels 
to request a backport and indicate approval or rejection.

Here is the procedure:

1. A developer makes the request by adding the "jfx23u-fix-request" 
label to the main bug in JBS (not the backport record, even presuming 
one exists), with a comment indicating that you would like to backport 
it, along with a justification and risk assessment, if needed.

2. One of the JavaFX projects leads, either Johan Vos or myself, will 
add a "jfx23u-fix-yes" label to approve or "jfx23u-fix-no" label to 
reject the request, along with a comment. In either case, the 
jfx23u-request label is left in place.

3. Create the backport PR for jfx23u, either manually or using the 
"/backport" command. If you have good reason to believe that that this 
bug is a good candidate for jfx23u, then you can do this step first and 
use Skara's "/approval" command to request approval.

Let Johan or me know if you have any questions.

Thanks.

-- Kevin

[1] https://github.com/openjdk/jfx23u
[2] https://github.com/openjdk/jfx/tree/jfx23