Private IBAction is reported as unused in SPM

[SmallRedGollum]

Describe the bug
Private IBAction methods inside an SPM module are incorrectly reported as unused by Periphery
The issue reproduces on the latest version (3.6.0)

Steps to reproduce

• Use Periphery 3.6.0

• Analyze an SPM module containing a UIViewController with IBAction methods

• Observe that private IBActions connected via Interface Builder are flagged as unused

Minimal reproducible example:
https://github.com/SmallRedGollum/PeripheryIBActionWarning/blob/main/Sources/PeripheryIBActionWarning/ViewController.swift

Scan

periphery scan --config "./periphery.yml" --skip-build --index-store-path "/path/DerivedData/PeripheryIBActionWarning/Index.noindex/DataStore"

Output

/path/PeripheryIBActionWarning/ViewController.swift:17:28: warning: Unused function 'onButtonDidTap()'

/path/PeripheryIBActionWarning/ViewController.swift:30:20: warning: Unused function 'onButtonDidTap2()'

Expected behavior
Private IBAction methods connected in Interface Builder should not be reported as unused