ci: run packaging if .go-version/Dockefile changes

[v1v]

What does this PR do?

Run packaging on PRs if:

• .go-version changes
• Dockerfile changes

Why is it important?

Validate golang-crossbuild docker images are in place

Otherwise, #2475 (comment)

[ycombinator]

LGTM.

[elasticmachine]

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• Start Time: 2023-04-19T13:11:25.164+0000

• Duration: 66 min 35 sec

Test stats 🧪

Test	Results
Failed	0
Passed	11038
Skipped	40
Total	11078

💚 Flaky test report

Tests succeeded.

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To re-run your PR in the CI, just comment with:

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[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.529% (67/68)	👍
Files	68.22% (161/236)	👍
Classes	67.785% (303/447)	👍
Methods	54.111% (928/1715)	👍
Lines	39.626% (10508/26518)	👍 0.038
Conditionals	100.0% (0/0)	💚