add container spec args to to go debug

[tejal29]

Description
When setting up skaffold for kaniko, skaffold debug failed with following error"

failed to port forward pod-kaniko-default-56268, port 56268 is taken, retrying...
time="2019-11-20T13:36:31-08:00" level=debug msg="terminated pod-kaniko-default-56268 due to context cancellation"
[kaniko] Error: unknown flag: --no-push
[kaniko] Usage:
[kaniko]   dlv exec <path/to/binary> [flags]
[kaniko] 
[kaniko] Flags:
[kaniko]       --continue   Continue the debugged process on start.
[kaniko] 
[kaniko] Global Flags:
[kaniko]       --accept-multiclient   Allows a headless server to accept multiple client connections.
[kaniko]       --api-version int      Selects API version when headless. (default 1)
[kaniko]       --backend string       Backend selection (see 'dlv help backend'). (default "default")
[kaniko]       --build-flags string   Build flags, to be passed to the compiler.
[kaniko]       --check-go-version     Checks that the version of Go in use is compatible with Delve. (default true)
[kaniko]       --headless             Run debug server only, in headless mode.
[kaniko]       --init string          Init file, executed by the terminal client.
[kaniko]   -l, --listen string        Debugging server listen address. (default "127.0.0.1:0")
[kaniko]       --log                  Enable debugging server logging.
[kaniko]       --log-dest string      Writes logs to the specified file or file descriptor (see 'dlv help log').
[kaniko]       --log-output string    Comma separated list of components that should produce debug output (see 'dlv help log')
[kaniko]       --wd string            Working directory for running the program. (default ".")
[kaniko] 
Port forwarding pod/kaniko in namespace default, remote port 56268 -> local port 56268

User facing changes
No

Debug Transformation Changes
Before
The container spec generated when debugging was

tejaldesai@@kaniko (add_skaffold)$ kubectl describe po/kaniko
Name:               kaniko
...
  kaniko:
    Container ID:  docker://ee1994b1b80eeb06ba8c506b3cf4b43410ef4ad1372d0559c03098c9ff488303
    Image:         gcr.io/tejal-test/gcr.io/kaniko-project/executor:v0.14.0-7-ge0e59e6-dirty@sha256:7a204497053998c62c69feb1f9b7bbbad92f5e9e9738d1a4147c841b6cb60204
    Image ID:      docker-pullable://gcr.io/tejal-test/gcr.io/kaniko-project/executor@sha256:7a204497053998c62c69feb1f9b7bbbad92f5e9e9738d1a4147c841b6cb60204
    Port:          56268/TCP
    Host Port:     0/TCP
    Command:
      /dbg/go/bin/dlv
      exec
      --headless
      --continue
      --accept-multiclient
      --listen=localhost:56268
      --api-version=2
      /go/src/github.com/GoogleContainerTools/kaniko/out/executor
    Args:
      --no-push
      --context=dir://workspace/
      --dockerfile=integration/dockerfiles/Dockerfile_test_add
....

After
After this PR, we now have -- added at the end

tejaldesai@@kaniko (add_skaffold)$ kubectl describe po/kaniko
Name:               kaniko
...
Containers:
  kaniko:
    Container ID:  docker://ee1994b1b80eeb06ba8c506b3cf4b43410ef4ad1372d0559c03098c9ff488303
    Image:         gcr.io/tejal-test/gcr.io/kaniko-project/executor:v0.14.0-7-ge0e59e6-dirty@sha256:7a204497053998c62c69feb1f9b7bbbad92f5e9e9738d1a4147c841b6cb60204
    Image ID:      docker-pullable://gcr.io/tejal-test/gcr.io/kaniko-project/executor@sha256:7a204497053998c62c69feb1f9b7bbbad92f5e9e9738d1a4147c841b6cb60204
    Port:          56268/TCP
    Host Port:     0/TCP
    Command:
      /dbg/go/bin/dlv
      exec
      --headless
      --continue
      --accept-multiclient
      --listen=localhost:56268
      --api-version=2
      /go/src/github.com/GoogleContainerTools/kaniko/out/executor
      --
    Args:
      --no-push
      --context=dir://workspace/
      --dockerfile=integration/dockerfiles/Dockerfile_test_add

Next PRs.
n/a
Submitter Checklist

These are the criteria that every PR should meet, please check them off as you
review them:

• Includes unit tests
• Mentions any output changes.
• Adds documentation as needed: user docs, YAML reference, CLI reference.
• Adds integration tests if needed.

Reviewer Notes

• The code flow looks good.
• Unit test added.
• User facing changes look good.

Release Notes

Fix `skaffold debug` when go application have an entrypoint with arguments set.

[codecov]

Codecov Report

Merging #3276 into master will not change coverage.
The diff coverage is 100%.

Impacted Files	Coverage Δ
pkg/skaffold/debug/transform_go.go	86.17% <100%> (ø)	⬆️

[briandealwis]

Oooo good find