Post-release bug database clean up

[Rik]

There are a bunch of bugs that probably refer to old versions of Octave, with old versions of hardware that no longer exist, etc.

How do we want to handle these?  I know some code projects just go through and close all bugs related to older versions.  That might be a little extreme for us, but I still think a lot of these could be culled.  An alternative proposal would be to respond on the various old bug reports asking the original reporter to re-test with either the RC2 candidate or the 5.1 release when it is out.  If no response in some amount of time (1 week?) then just close the report?

Either way, this culling is a lot of work and if others could help identify these bugs and get them started on the path towards closure that would help.

--Rik

Here are some ones that I found

Owner: ??? #55053 GUI hanging when editing and saving function file during debugging
Owner: ??? #54708 Segfault closing plot fig on precompiled octave on Mojave
Owner: ??? #54507 Segfault in QT5 when resizing window during initialization
Owner: ??? #54431 GUI crashes on workspace refresh while executing script
Owner: ??? #53207 crash when Octave starts on Windows after removing external 4K display
Owner: ??? #53115 "octave exited with signal 6" on attempt to stop debugging
Owner: ??? #52996 calling audiodevinfo() results in a segfault on exit when JACK sound server is running
Owner: ??? #50430 plot function causes crash/termination of Octave (Windows)
Owner: ??? #50025 Octave window freezes when I quit Octave GUI
Owner: ??? #49758 octave-cli crashes when closing fullscreen plot