Fix "cf_pass is not set" on first pipeline run
Fix "cf_pass is not set" on first pipeline run

The first time the `create-cloudfoundry` pipeline runs, it doesn't have
a value for `cf_pass` in credhub. This is required in the `pre-deploy`
step, which causes the pipeline to fail.

Ordinarily `cf_pass` would be generated by bosh as part of `cf-deploy`,
but since that happens later it's not much help.

Instead, this commit adds a task to generate secrets which uses credhub
to generate a value for the cf admin password (in the bosh namespace),
using the `--no-overwrite` flag to prevent this from clobbering the old
value. It then copies this secret from the bosh namespace to the
concourse namespace so it can be used in the pipeline.

alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf