refactor(@angular-devkit/build-angular): use high resolution time for esbuild builder completion time

Update the build time calculation for the experimental esbuild-based browser application builder to
use the `process.hrtime` time source.  The high resolution time provides a more accurate time source
and allows for nanosecond level timings if needed.  Currently the console output is rounded to the
nearest millisecond. Future performance monitoring capabilities may leverage the more fine-grained
values.

Author: clydin

packages/angular_devkit/build_angular/src/builders/browser-esbuild/index.ts

@@ -69,7 +69,7 @@ async function execute(
   context: BuilderContext,
   rebuildState?: RebuildState,
 ): Promise<ExecutionResult> {
-  const startTime = Date.now();
+  const startTime = process.hrtime.bigint();
 
   const {
     projectRoot,
@@ -206,7 +206,8 @@ async function execute(
     }
   }
 
-  context.logger.info(`Complete. [${(Date.now() - startTime) / 1000} seconds]`);
+  const buildTime = Number(process.hrtime.bigint() - startTime) / 10 ** 9;
+  context.logger.info(`Complete. [${buildTime.toFixed(3)} seconds]`);
 
   return new ExecutionResult(true, codeResults.rebuild, codeBundleCache);
 }