add version command and ldflags

[cpanato]

What type of PR is this?

/kind feature

What this PR does / why we need it:

• add version command and ldflags

to help in debug and inform the user which version they are using

$ ./output/bom-darwin-amd64 version
______  ________  ___
| ___ \|  _  |  \/  |
| |_/ /| | | | .  . |
| ___ \| | | | |\/| |
| |_/ /\ \_/ / |  | |
\____/  \___/\_|  |_/
bom: A tool for working with SPDX manifests

GitVersion:    v0.1.0-64-ga8d39d8
GitCommit:     a8d39d8
GitTreeState:  dirty
BuildDate:     2022-01-22T17:25:52Z
GoVersion:     go1.17.6
Compiler:      gc
Platform:      darwin/amd64

/assign @puerco @justaugustus @xmudrii @Verolop @saschagrunert
cc @kubernetes-sigs/release-engineering

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?

[cpanato]

using the doom font > bom doom
/joke

[k8s-ci-robot]

@cpanato: My friend told me that pepper is the best seasoning for a roast, but I took it with a grain of salt.

In response to this:

using the doom font > bom doom
/joke

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.

[justaugustus]

@cpanato -- Approving to move this along, but...

I feel like we write a version package/version for multiple projects. Could we abstract/de-dupe?

Consider writing this as a package in sigs.k8s.io/release-utils that can be an importable cobra.Command.

See https://github.com/kubernetes/enhancements/tree/master/pkg/kepctl/commands for an example, as well @n3wscott's comments in kubernetes/enhancements#2387 (review) for more background.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, justaugustus

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[justaugustus]

Consider writing this as a package in sigs.k8s.io/release-utils that can be an importable cobra.Command.

Created kubernetes-sigs/release-utils#23 to discuss.

[justaugustus]

GitHub reviews should act as /lgtm + /approve for SIG Release repos.
Filing an issue for this...
Original issue: kubernetes/sig-release#1464
Implementation example: kubernetes/test-infra#20934
cc: @kubernetes-sigs/release-engineering

/lgtm

[justaugustus]

Filing an issue for this...

#28