test: split test-esm-loader-hooks

Previously whenever one of the test case fails in the CI, it
barely logged anything useful in the CI and it was difficult to
nail down the specific failing case with a local reproduction,
especially when the test fixutre is inline JavaScript. This patch:

- Puts all the inline JavaScript in on-disk fixtures so that
  they can be re-run easily.
- Split the tests into individual files so that it's easier to nail
  down the failure
- Use spawnSyncAndAssert which logs useful information when the child
  process does not behave as expected.
- Rename the tests as module-hooks/test-async-loader-hooks-* because
  they belong to the module hooks test suite and are not esm-specific.

Author: joyeecheung

test/es-module/test-esm-loader-hooks.mjs

@@ -0,0 +1,3 @@
+export function load(a, b, c) {
+  return new Promise(d => setTimeout(() => d(c(a, b)), 99));
+}

test/fixtures/es-module-loaders/loader-delayed-async-load.mjs

@@ -0,0 +1,4 @@
+export function load(a, b, next) {
+  if (a === 'data:exit') process.exit(42);
+  return next(a, b);
+}

test/fixtures/es-module-loaders/loader-exit-on-load.mjs

@@ -0,0 +1,4 @@
+export function resolve(a, b, next) {
+  if (a === 'exit:') process.exit(42);
+  return next(a, b);
+}

test/fixtures/es-module-loaders/loader-exit-on-resolve.mjs

@@ -0,0 +1 @@
+process.exit(42);

test/fixtures/es-module-loaders/loader-exit-top-level.mjs

@@ -0,0 +1,2 @@
+export function globalPreload() {}
+export function initialize() {}

test/fixtures/es-module-loaders/loader-globalpreload-and-initialize.mjs

@@ -0,0 +1 @@
+export function globalPreload() {}

test/fixtures/es-module-loaders/loader-globalpreload-only.mjs

@@ -0,0 +1,3 @@
+export function globalPreload() {
+  return '';
+}

test/fixtures/es-module-loaders/loader-globalpreload-with-return.mjs

@@ -0,0 +1,3 @@
+export function initialize() {
+  process.exit(42);
+}

test/fixtures/es-module-loaders/loader-initialize-exit.mjs

@@ -0,0 +1,3 @@
+export function initialize() {
+  return new Promise(() => {});
+}