Show underlying type for type aliases

For example, [azblob/appendblob.ExpiryTypeAbsolute](https://pkg.go.dev/github.com/Azure/azure-sdk-for-go/sdk/storage/azblob@v1.4.0/appendblob#ExpiryTypeAbsolute) is an alias for an [internal type](https://pkg.go.dev/github.com/Azure/azure-sdk-for-go/sdk/storage/azblob@v1.4.0/internal/exported#ExpiryTypeAbsolute) having underlying type `time.Time`. The `appendblob` review should indicate this with an entry like `type ExpiryTypeAbsolute time.Time`

Start by locating the code that generates the appendblob review and tracing how type aliases are rendered. The work is done when the review shows an entry such as `type ExpiryTypeAbsolute time.Time` for the alias described in the issue, while preserving the referenced package context.

Written by the indexing model from the issue text.