Annotation("Npgsql:CreatedConcurrently", true) works but IsCreatedConcurrently(true) does not

[jonkelling]

Tested with the following versions:

    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="9.0.1" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.1">
    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="9.0.3" />

Steps to reproduce:

1. Add [Index(nameof(SomeColumn))] to an entity class
2. Run dotnet ef migrations add NewMigration
3. Update ..._NewMigration.Designer.cs to include b.HasIndex("SomeColumn").IsCreatedConcurrently(true).HasDatabaseName("ix_some_column");
4. Run dotnet ef migrations script -o dbupdate.sql
5. Observe that there is still an SQL transaction, and CREATE INDEX does not include CONCURRENTLY
6. Update ...NewMigration.cs to include migrationBuilder.CreateIndex(...).Annotation("Npgsql:CreatedConcurrently", true);
7. Run dotnet ef migrations script -o dbupdate.sql
8. Observe that the SQL transaction is gone and it now includes CREATE INDEX CONCURRENTLY