Bump Phan to 5.5.2

[tbradsha]

Closes MONOREP-151

Phan 5.5.1 had some bugs, so required a bunch of suppressions, and the entire disabling of two rules. Now that v5.5.2 is out, we can update to that and remove those suppressions, which is what this PR does.

It also caught a few new errors, which I address. This is probably the most important part to review.

Proposed changes:

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[github-actions]

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[jp-launch-control]

Code Coverage Summary

This PR did not change code coverage!

That could be good or bad, depending on the situation. Everything covered before, and still is? Great! Nothing was covered before? Not so great. 🤷

Full summary · PHP report · JS report

[manzoorwanijk]

Looks good. Just a couple of optional questions.

[manzoorwanijk]

This specific version without ^ is to match what we have at other places, right?

[manzoorwanijk]

Why not use the Null Coalescing Assignment Operator?

Suggested change

	$file['content'] = $file['content'] ?? '';
	$file['type'] = $file['type'] ?? 'application/octet-stream';
	$file['name'] = $file['name'] ?? '';
	$file['content'] ??= '';
	$file['type'] ??= 'application/octet-stream';
	$file['name'] ??= '';