sysutils/rubygem-bundler: Create symlinks for manpages

Manpages of bundler are installed in
${PREFIX}/${GEMS_BASE_DIR}/gems/${PORTNAME}-${PORTVERSION}/lib/bundler/man
but it isn't included in the default value of MANPATH. So create
symlinks to the manpages in ${PREFIX}/man/man{1,5} so man(1) can find them.

While here, pet portclippy.

PR: 272258
Approved by: maintainer timeout