Merge branch 'js/no-builtins-on-disk-option'

Merge branch 'js/no-builtins-on-disk-option'

The installation procedure learned to optionally omit "git-foo"
executable files for each 'foo' built-in subcommand, which are only
required by old timers that still rely on the age old promise that
prepending "git --exec-path" output to PATH early in their script
will keep the "git-foo" calls they wrote working.

The old attempt to remove these executables from the disk failed in
the 1.6 era; it may be worth attempting again, but I think it is
worth to keep this topic separate from such a policy change to help
it graduate early.

* js/no-builtins-on-disk-option:
  ci: stop linking built-ins to the dashed versions
  Optionally skip linking/copying the built-ins
  msvc: copy the correct `.pdb` files in the Makefile target `install`