update the output of install-etcd.sh, show how to export the environment of etcd

[suigh]

What type of PR is this?
/kind flake
/sig cli

What this PR does / why we need it:
To start a local/fake cluster, what we need to do is run "hack/install-etcd.sh" first and then run "hack/local-up-cluster.sh".

If the "install-etcd.sh" is executed before, what we get is like:
etcd v3.3.10 already installed at path:
/opt/src/k8s.io/kubernetes/third_party/etcd-v3.3.10-linux-amd64

This information is not enough/convenient to run "local-up-cluster.sh" again as user needs to set the the etcd information into environment variable PATH before running this command. The current output is not user friendly to a new kubernetes user (like me).

To fix this issue, the new message will be as following when the etcd is already installed:
etcd v3.3.10 already installed. To use:
export PATH=/opt/src/k8s.io/kubernetes/third_party/etcd:${PATH}

Which issue(s) this PR fixes:
Fixes # NONE

Does this PR introduce a user-facing change?:
NONE

[k8s-ci-robot]

Hi @suigh. Thanks for your PR.

I'm waiting for a kubernetes 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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Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[neolit123]

/release-note-none
/ok-to-test
/priority backlog

[neolit123]

thanks for the PR @suigh
/assign @dims

[neolit123]

/release-note-none

[dims]

/approve
/lgtm

[cblecker]

/hold

[dims]

/hold

for @cblecker 's comments

[cblecker]

/test all

[cblecker]

/retest

[cblecker]

@suigh Things look good! Last step: can you please squash your commits, and update your commit message to be descriptive of the change?

Thanks!

[suigh]

@cblecker thanks for your suggestion. Update/merge the commit message to
"update the output of install-etcd.sh, show how to export the environment of etcd."

@suigh Things look good! Last step: can you please squash your commits, and update your commit message to be descriptive of the change?

Thanks!

[cblecker]

/lgtm
/approve
/hold cancel

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cblecker, dims, suigh

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• hack/OWNERS [cblecker,dims]

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