[xextension] Add deprecated type alias support for extensions
Add support for deprecated component type aliases to extensions, following the implementation started in #14349
The new `xextension.WithDeprecatedTypeAlias` factory option allows extension authors to register deprecated type aliases using:
```go
xextension.NewFactory(
newType,
createDefaultConfig,
createExtension,
component.StabilityLevelAlpha,
xextension.WithDeprecatedTypeAlias(oldType),
)