Update vcpkg GitHub Action

Update vcpkg GitHub Action

- Update vcpkg to current 2025.12.12 Release, commit 84bab45
- Current versions of libraries are e.g.:
  cairo 1.18.4, expat 2.7.3, fontconfig 2.17.1, freetype 2.13.3,
  gettext 0.22.5, glib 2.86.2, libpng 1.6.53, pango 1.56.4,
  pcre2 10.47, libxml2 2.15.1 and zlib 1.3.1
- Github actions:
  * Switch from `lukka/run-vcpkg` to `johnwason/vcpkg-action`
  * Update `actions/checkout` from v4 to v6
  * Update `actions/upload-artifact` from v4 to v6
- `win32/collect_rrdtool_vcpkg_files.bat`:
  Remove `liblzma.dll`, as deprecated feature lzma has been removed
  from libxml2 in vcpkg.
  See: https://github.com/microsoft/vcpkg/pull/47380