Fixes build step

build.js

@@ -365,6 +365,7 @@ export async function bundleCombinedWorkers(options) {
   thirdPartyWorkerConfig.entryPoints = thirdPartyWorkers;
   thirdPartyWorkerConfig.outdir = options.path;
   thirdPartyWorkerConfig.minify = options.minify;
+  thirdPartyWorkerConfig.outbase = "Source";
   await esbuild.build(thirdPartyWorkerConfig);
 
   // Bundle ES6 workers.
@@ -426,18 +427,6 @@ export async function bundleWorkers(options) {
   workerConfig.minify = options.minify;
   await esbuild.build(workerConfig);
 
-  // Copy ThirdParty workers
-  const thirdPartyWorkers = await globby(["Source/ThirdParty/Workers/**"]);
-
-  const thirdPartyWorkerConfig = defaultESBuildOptions();
-  thirdPartyWorkerConfig.entryPoints = thirdPartyWorkers;
-  thirdPartyWorkerConfig.outdir = options.path;
-  thirdPartyWorkerConfig.outbase = `packages/engine/Source`; // Maintain existing file paths
-  thirdPartyWorkerConfig.minify = options.minify;
-  // We don't want the CesiumJS copyright banner added to the ThirdParty worker files.
-  thirdPartyWorkerConfig.banner = undefined;
-  await esbuild.build(thirdPartyWorkerConfig);
-
   // Use rollup to build the workers:
   // 1) They can be built as AMD style modules
   // 2) They can be built using code-splitting, resulting in smaller modules