pass back exit status from coverage child process to parent

src/index.js

@@ -2,7 +2,7 @@ import path from "path";
 import fs from "fs";
 import { fileURLToPath } from "url";
 import readline from "readline";
-import { spawn } from "child_process";
+import { spawnSync } from "child_process";
 import getFiles from "./getFiles.js";
 import runTests from "./runTests.js";
 import flattenTests from "./flattenTests.js";
@@ -48,14 +48,14 @@ export default options => {
  coverage
  } = options;
  if (coverage) {
- spawn(
+ const { status } = spawnSync(
  `npx --yes c8 --reporter=text --reporter=lcov node ${__dirname}/tead.js "--testPattern=${testPattern}"`,
  {
  shell: true,
  stdio: "inherit"
  }
  );
- return;
+ process.exit(status);
  }
  const testFilter = filename => filename.match(new RegExp(testPattern));
  const watchFilter = filename => filename.match(new RegExp(watchPattern));