fix missing semicolons to struct fields in .d.ts

TypeScript class property requires semicolon at the end:
    https://www.typescriptlang.org/docs/handbook/classes.html

crates/cli-support/src/js/mod.rs

@@ -2514,7 +2514,7 @@ impl<'a, 'b> SubContext<'a, 'b> {
                     .argument(&descriptor)?
                     .ret(&Descriptor::Unit)?;
                 ts_dst.push_str(&format!(
-                    "{}{}: {}\n",
+                    "{}{}: {};\n",
                     if field.readonly { "readonly " } else { "" },
                     field.name,
                     &cx.js_arguments[0].1