packer_cache: avoid failing

[v1v]

What does this pull request do?

Avoid failing while tagging and avoid pulling/tagging docker images with a comment (#)

Issue

Leftover from the original attempt in #1516

[ghost]

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Build stats

• Start Time: 2022-04-20T15:05:02.321+0000

• Duration: 23 min 48 sec

Test stats 🧪

Test	Results
Failed	0
Passed	4829
Skipped	3293
Total	8122

💚 Flaky test report

Tests succeeded.

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