Refactoring fake component and shipper codebases

[ycombinator]

What does this PR do?

This PR refactors the fake component and shipper codebases, in preparation for #2218.

Why is it important?

To reduce noise in #2218, hopefully making it a bit easier to review.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool

Author's Checklist

• [ ]

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• Start Time: 2023-03-20T16:53:10.034+0000

• Duration: 17 min 49 sec

Test stats 🧪

Test	Results
Failed	0
Passed	5003
Skipped	15
Total	5018

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.387% (61/62)	👍
Files	68.868% (146/212)	👍
Classes	67.98% (276/406)	👍
Methods	53.455% (851/1592)	👍
Lines	38.802% (9429/24300)	👎 -0.037
Conditionals	100.0% (0/0)	💚