Update dev-tools to support Go Workspace

[belimawr]

What does this PR do?

This commit updates the dev-tool code to support Go Workspace.

Why is it important?

Go Workspaces facilitates working on multiple modules at the same time, Elastic-Agent and Beats share a number of modules and sometimes it's necessary to change more than one at once.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas~~
  ~~- [ ] I have added tests that prove my fix is effective or that my feature works
  - [ ] I have added an entry in CHANGELOG.md

How to test this PR locally

1. Clone elastic-agent, beats and elastic-agent-libs on the same folder
2. Create a multi-module workspace: go work init
3. Add all 3 modules to the workspace:

   go work use elastic-agent beats elastic-agent-libs
   

4. Build the Elastic-Agent (set PLATFORMS according to your platform)

   DEV=true SNAPSHOT=true EXTERNAL=false PLATFORMS="linux/amd64" PACKAGES="tar.gz" mage -v package
   

5. The build should succeed

## Related issues

[elasticmachine]

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Build stats

• Start Time: 2023-05-23T10:58:58.831+0000

• Duration: 9 min 47 sec

Test stats 🧪

Test	Results
Failed	0
Passed	787
Skipped	5
Total	792

🤖 GitHub comments

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[ycombinator]

Do we need -buildvcs=false here? AFAICT it's not an option supported by go list. It looks like that option is only supported by go build. Also, running just go list -f {{.Module}} seems to work.

Suggested change

	lines, err := getLines(callGo(nil, "list", "-buildvcs=false", "-f", "{{.Module}}"))
	lines, err := getLines(callGo(nil, "list", "-f", "{{.Module}}"))