fix(ci): request ARG in every build stage

[pront]

Summary

ARG needs to be requested in every build stage

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

How did you test this PR?

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the "no-changelog" label to this PR.

Notes

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References

[datadog-vectordotdev]

Datadog Report

Branch report: pront/tiny-fix-dockerfile
Commit report: 63175cb
Test service: vector

✅ 0 Failed, 7 Passed, 0 Skipped, 25.43s Total Time

[bfung]

As I read https://docs.docker.com/reference/dockerfile/#understand-how-arg-and-from-interact , seems like it'll work.