bump topgun
bump topgun

Submodule src/github.com/concourse/topgun 70e11a42..1d2891ec:
  > Merge branch 'releases/2.7'
  > delete old cache volumes when new resource version
  > add tests for inactive resource
  > unpend bind mount certificates test
  > fix http proxy + image artifact tests
  > fix package name
  > move image artifact tests from testflight
  > move proxy test over from testflight
  > localize var
  > fix containers_scoped_to_team_test
  > Revert "unpend hijack check container test"
  > query containers via fly, not database
  > unfocus :(
  > add test for tagged resource checking
  > darwin captures whitespace here
  > unpend hijack check container test
  > pend bind mounts test
  > Merge branch 'releases/2.7'
  > pend atc shutdown test
  > added support for an arbitary number of topgun networks
  > Randomizing the topgun deployment name
  > force stringification of stemcell version
  > test transferring artifacts between workers
  > fix topgun test for atc shutdown
  > resource_caches > worker_resource_caches
  > skip hijacking to check containers test
  > only task containers are kept around
  > hijacking a task no longer asks about check/get
  > validate getting containers succeeds

Signed-off-by: Clara Fu <d5c8bdbc15689555c92563892e959c79b3fc425f@pivotal.io>

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse