Fix backtrace for running the bundle’s own specs.
Fix backtrace for running the bundle’s own specs.

When running the bundle’s own specs *all* backtrace lines got filtered out, so that RSpec showed the complete backtrace as a fallback.

infininight/rspec-tmbundle,infininight/rspec-tmbundle,die-antwort/rspec-tmbundle,rspec/rspec.tmbundle,die-antwort/rspec-tmbundle,rspec/rspec.tmbundle