Generate Equatable conformance for empty FlagContainers

[bok-]

📒 Description

We currently skip generating Equatable conformance inside @FlagContainer if the declaration is empty (has no stored properties). This is different from the synthesised conformance to Equatable that the compiler generates, as described in SE-0185:

A struct T: Equatable that satisfies the conditions above will receive a synthesized implementation of static func == (lhs: T, rhs: T) -> Bool that returns true if and only if lhs.x == rhs.x for all stored properties x in T. If the struct has no stored properties, this operator simply returns true.

Currently, this means empty @FlagContainers that appear any where in a flag hierarchy breaks generated Equatable conformance for the entire hierarchy.

This PR updates @FlagContainer to generate Equatable conformance inline with the behaviour described in SE-0185.

🗳 Test Plan

Covered by unit tests and compilation tests.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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