tests: virjson: Reuse VIR_TEST_VERBOSE in testJSONCopy
tests: virjson: Reuse VIR_TEST_VERBOSE in testJSONCopy

Use VIR_TEST_VERBOSE instead of calling virTestGetVerbose and
conditionally fprintf. Additionally remove redundant setting of 'ret' to
-1.

eskultety/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,libvirt/libvirt,jfehlig/libvirt,andreabolognani/libvirt,eskultety/libvirt,zippy2/libvirt,libvirt/libvirt,eskultety/libvirt,andreabolognani/libvirt,datto/libvirt,datto/libvirt,nertpinx/libvirt,zippy2/libvirt,libvirt/libvirt,datto/libvirt,nertpinx/libvirt,jardasgit/libvirt,datto/libvirt,jfehlig/libvirt,zippy2/libvirt,crobinso/libvirt,crobinso/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,crobinso/libvirt,fabianfreyer/libvirt,eskultety/libvirt,olafhering/libvirt,jardasgit/libvirt,jardasgit/libvirt,olafhering/libvirt,nertpinx/libvirt,nertpinx/libvirt,datto/libvirt,andreabolognani/libvirt,jfehlig/libvirt,zippy2/libvirt,jfehlig/libvirt,olafhering/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,jardasgit/libvirt,crobinso/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,eskultety/libvirt,libvirt/libvirt,olafhering/libvirt