Please advice for create a package with no soversion specified

[Daisuke Fujimura]

I'm trying to create a package for googletest, but no soversion is
specified in the original source.

- https://github.com/google/googletest/issues/3113

What soversion should I set if I want to set my own soversion in
cygwin with no soversion specified?

1. 0 (default for autotools)
    - https://github.com/OpenMandrivaAssociation/gtest/blob/master/googletest-1.8.0-sonames.patch
2. 1.10.0 (software version)
    - https://www.archlinux.org/packages/community/x86_64/gtest/
3. other than the above
    - https://packages.debian.org/bullseye/amd64/libgtest-dev/filelist
(provide static only)