d.git.sample-gitconfig: fix :stag, :sbr

The old :stag ignore the tag with release number (foobar-1.2.3-4)
because of a strict check. However, we can not add, for example,
"(-[0-9]+)?" to the regexp. which cause some errors. Using shell
in git alias is very limited :(

We also remove the dollar sign ($) from #sbr. It is non-sense