Add /tmp dir to example registry-server image

[joelsmith]

Description of the change:

Creates /tmp directory in example registry-server image build.

Motivation for the change:

Apparently a change in registry-server requires the existence of the /tmp directory. The example Dockerfile should create /tmp so that images built from it don't result in crashing containers, like this:

$ oc logs -n openshift-marketplace my-manifests-f4klp
Error: open /tmp/db-425155909: no such file or directory
Usage:
   [flags]

Flags:
  -d, --database string          relative path to sqlite db (default "bundles.db")
  -h, --help                     help for this command
  -p, --port string              port number to serve on (default "50051")
      --skip-migrate             do  not attempt to migrate to the latest db revision when starting
  -t, --termination-log string   path to a container termination log file (default "/dev/termination-log")

time="2020-05-29T16:49:40Z" level=panic msg="open /tmp/db-425155909: no such file or directory"
panic: (*logrus.Entry) (0x1084020,0xc0001c2070)

goroutine 1 [running]:
github.com/sirupsen/logrus.Entry.log(0xc0000c8000, 0xc00019d290, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
        /build/vendor/github.com/sirupsen/logrus/entry.go:239 +0x2db
github.com/sirupsen/logrus.(*Entry).Log(0xc0001c2000, 0xc000000000, 0xc00011df40, 0x1, 0x1)
        /build/vendor/github.com/sirupsen/logrus/entry.go:268 +0xeb
github.com/sirupsen/logrus.(*Logger).Log(0xc0000c8000, 0x0, 0xc00011df40, 0x1, 0x1)
        /build/vendor/github.com/sirupsen/logrus/logger.go:192 +0x7d
github.com/sirupsen/logrus.(*Logger).Panic(...)
        /build/vendor/github.com/sirupsen/logrus/logger.go:233
github.com/sirupsen/logrus.Panic(...)
        /build/vendor/github.com/sirupsen/logrus/exported.go:129
main.main()
        /build/cmd/registry-server/main.go:51 +0xbe

Reviewer Checklist

• Implementation matches the proposed design, or proposal is updated to match implementation
• Sufficient unit test coverage
• Sufficient end-to-end test coverage
• Docs updated or added to /docs
• Commit messages sensible and descriptive

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: joelsmith
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[openshift-ci-robot]

Hi @joelsmith. Thanks for your PR.

I'm waiting for a operator-framework member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[exdx]

/ok-to-test
I think this may have been introduced by #332 - we recently started making copies of the index DB to avoid permissions issues when running migrations.

[exdx]

/lgtm

[awgreene]

/lgtm

[Bowenislandsong]

/retest

[Bowenislandsong]

/lgtm

[joelsmith]

/hold
It seems like this PR will be unneeded if #343 merges.

[ecordell]

Fixed by #353