cmake: rename crimson tests named like foo_bar to foo-bar

cmake: rename crimson tests named like foo_bar to foo-bar

for two reasons:

* less typing: no need to press "shift" for inputting "_"
* more consistent with executable names like "ceph-conf"
* simpler to grep when compiling the tests. there is chance
  we need to kill the dead jobs on a jenkins worker node
  where it happens to be compiling the tests.

Signed-off-by: Kefu Chai <kchai@redhat.com>