use /client for react-dom (#1872)

Author: mbostock

src/npm.ts

@@ -267,6 +267,8 @@ export async function resolveNpmImport(root: string, specifier: string): Promise
       ? "dist/jquery-ui.js/+esm"
       : name === "deck.gl"
       ? "dist.min.js/+esm"
+      : name === "react-dom"
+      ? "client"
       : "+esm"
   } = parseNpmSpecifier(specifier);
   const version = await resolveNpmVersion(root, {name, range});