ci: adopt GitReleaseNoteGenerator and nbgv CLI tool (#1125)

- Replace the glennawatson/ChangeLog action with the GitReleaseNoteGenerator
  global tool (git-release-notes) to produce release notes, matching the
  reactiveui pipeline. Resolves #1093.
- Swap the stale dotnet/nbgv JS action for the nbgv global tool, stamping
  cloud variables via `nbgv cloud -a` and exposing SemVer2/PrereleaseVersion
  as step outputs.
- Keep Nerdbank.GitVersioning (version.json) as the version source; all
  branch/version policy checks are unchanged.

Fixed that the Build and Release action defined in release.yml was at…

…tempting to publish a bogus "empty.nupkg" file that exists in the normal build output of the DynamicData.Tests project, as a part of the EmptyFiles package, since the job was written to search for "*.nupkg". (#1124)

The job has been adjusted to only look for "DynamicData.*.nupkg" files.

(cherry picked from commit efc077c)

Rewrote the list variant of the OnItemRemoved() operator, in accordan…

…ce with #1014, as a fix for #1062. (#1067)

Bump version to 9.4 (#1016)

Use new lock primitive (#1005)

* Use new lock primitive
* Fix Git Actions PR warnings
* Simplify Synchronize implementation

Bump version for release (#1003)

Bug Fix: Virtual sort on same page (#997)

* Performance improvement for sort and virtualize / sort and page
* Fix comparer not applying for virtual sort when the data set is smaller then the virtual  page

Release v9.2 (#989)

Fix sort exception when using binary search (#984)

* Fix sort exception when using binary search

Bump version to 9.1 for release (#977)