Fix command typealias unwrapping in resolveType (#1449)

The loop unwraps nullables and constraints but breaks straight away
after a `typealias`. This means the nullable is missed. Removing the
`break` fixes it.

## Exception

```
org.pkl.core.PklException: –– Pkl Error ––
Command option property `foo` has unsupported type `String?`.

11 | foo: OptionalString
     ^^^^^^^^^^^^^^^^^^^
at <unknown> (file:///var/folders/xh/lmp1n6qj4m13t53cfmbqnkwh0000gn/T/junit-1378070630576324311/cmd.pkl)

Use a supported type or define a transformEach and/or transformAll function
```

pkl-core/src/main/java/org/pkl/core/runtime/CommandSpecParser.java

@@ -407,7 +407,6 @@ public final class CommandSpecParser {
       } else if (typeNode instanceof TypeNode.TypeAliasTypeNode typeAliasTypeNode) {
         if (typeAliasTypeNode.getVmTypeAlias() == BaseModule.getCharTypeAlias()) break;
         typeNode = typeAliasTypeNode.getAliasedTypeNode();
-        break;
       } else {
         break;
       }