Module exported variables should not be flagged with PSUseDeclaredVarsMoreThanAssignment

Repro: In a module, define and assign a variable then export it using Export-ModuleMember -Variable

$MyVariable = 'some value'
Export-ModuleMember -Variable MyVariable

Expected: Invoke-ScriptAnalyzer does not flag the variable as unused.
Actual:
file: 'file:MyModule.psm1'
severity: 'Warning'
message: 'The variable 'MyVariable' is assigned but never used. (PSUseDeclaredVarsMoreThanAssignments)'

首先使用 MyModule.psm1 示例复现该问题：为 MyVariable 赋值，并使用 Export-ModuleMember -Variable 导出它。跟踪 PSUseDeclaredVarsMoreThanAssignments 规则及其现有测试，然后验证导出的模块变量不再被报告为已赋值但从未使用。