test: reduce flakiness of test-runner-output.mjs

This commit is similar to nodejs#51952. When the system is under load
it is possible for these timeout tests to become flaky. We
work around that by using a much longer setTimeout() in the test
so that it is not racing against the test's timeout. But, we have
to unref() such a large timeout. And, because test timeouts do
not currently keep the event loop alive, we use a different
setTimeout() for that purpose.

Fixes: nodejs#52139
Refs: nodejs#52140

test/fixtures/test-runner/output/lcov_reporter.snapshot

@@ -81,24 +81,26 @@ FN:310,anonymous_77
 FN:313,anonymous_78
 FN:318,anonymous_79
 FN:319,anonymous_80
-FN:324,anonymous_81
-FN:329,anonymous_82
-FN:330,anonymous_83
+FN:320,anonymous_81
+FN:327,anonymous_82
+FN:328,anonymous_83
 FN:335,anonymous_84
-FN:339,anonymous_85
-FN:342,get then
+FN:336,anonymous_85
+FN:341,anonymous_86
 FN:345,anonymous_87
-FN:350,anonymous_88
-FN:353,get then
+FN:348,get then
+FN:351,anonymous_89
 FN:356,anonymous_90
-FN:361,anonymous_91
+FN:359,get then
 FN:362,anonymous_92
-FN:363,anonymous_93
-FN:367,anonymous_94
-FN:368,anonymous_95
-FN:369,anonymous_96
-FN:375,anonymous_97
-FN:379,anonymous_98
+FN:367,anonymous_93
+FN:368,anonymous_94
+FN:369,anonymous_95
+FN:373,anonymous_96
+FN:374,anonymous_97
+FN:375,anonymous_98
+FN:381,anonymous_99
+FN:385,anonymous_100
 FNDA:1,anonymous_0
 FNDA:1,anonymous_1
 FNDA:1,anonymous_2
@@ -185,21 +187,23 @@ FNDA:1,anonymous_82
 FNDA:1,anonymous_83
 FNDA:1,anonymous_84
 FNDA:1,anonymous_85
-FNDA:1,get then
+FNDA:1,anonymous_86
 FNDA:1,anonymous_87
-FNDA:1,anonymous_88
 FNDA:1,get then
+FNDA:1,anonymous_89
 FNDA:1,anonymous_90
-FNDA:1,anonymous_91
+FNDA:1,get then
 FNDA:1,anonymous_92
 FNDA:1,anonymous_93
 FNDA:1,anonymous_94
 FNDA:1,anonymous_95
 FNDA:1,anonymous_96
 FNDA:1,anonymous_97
 FNDA:1,anonymous_98
-FNF:99
-FNH:96
+FNDA:1,anonymous_99
+FNDA:1,anonymous_100
+FNF:101
+FNH:98
 BRDA:1,0,0,1
 BRDA:8,1,0,1
 BRDA:12,2,0,1
@@ -279,30 +283,32 @@ BRDA:310,75,0,1
 BRDA:313,76,0,1
 BRDA:318,77,0,1
 BRDA:319,78,0,1
-BRDA:324,79,0,1
-BRDA:329,80,0,1
-BRDA:330,81,0,1
+BRDA:320,79,0,1
+BRDA:327,80,0,1
+BRDA:328,81,0,1
 BRDA:335,82,0,1
-BRDA:339,83,0,1
-BRDA:342,84,0,1
-BRDA:343,85,0,0
-BRDA:345,86,0,1
-BRDA:350,87,0,1
-BRDA:353,88,0,1
-BRDA:354,89,0,0
-BRDA:356,90,0,1
-BRDA:361,91,0,1
-BRDA:364,92,0,0
-BRDA:362,93,0,1
-BRDA:363,94,0,1
-BRDA:367,95,0,1
-BRDA:370,96,0,0
-BRDA:368,97,0,1
-BRDA:369,98,0,1
-BRDA:375,99,0,1
-BRDA:379,100,0,1
-BRF:101
-BRH:97
+BRDA:336,83,0,1
+BRDA:341,84,0,1
+BRDA:345,85,0,1
+BRDA:348,86,0,1
+BRDA:349,87,0,0
+BRDA:351,88,0,1
+BRDA:356,89,0,1
+BRDA:359,90,0,1
+BRDA:360,91,0,0
+BRDA:362,92,0,1
+BRDA:367,93,0,1
+BRDA:370,94,0,0
+BRDA:368,95,0,1
+BRDA:369,96,0,1
+BRDA:373,97,0,1
+BRDA:376,98,0,0
+BRDA:374,99,0,1
+BRDA:375,100,0,1
+BRDA:381,101,0,1
+BRDA:385,102,0,1
+BRF:103
+BRH:99
 DA:1,1
 DA:2,1
 DA:3,1
@@ -702,6 +708,12 @@ DA:396,1
 DA:397,1
 DA:398,1
 DA:399,1
-LH:397
-LF:399
+DA:400,1
+DA:401,1
+DA:402,1
+DA:403,1
+DA:404,1
+DA:405,1
+LH:403
+LF:405
 end_of_record

test/fixtures/test-runner/output/output.js

@@ -317,12 +317,18 @@ test('subtest sync throw fails', async (t) => {
 
 test('timed out async test', { timeout: 5 }, async (t) => {
   return new Promise((resolve) => {
-    setTimeout(resolve, 100);
+    setTimeout(() => {
+      // Empty timer so the process doesn't exit before the timeout triggers.
+    }, 5);
+    setTimeout(resolve, 30_000_000).unref();
   });
 });
 
 test('timed out callback test', { timeout: 5 }, (t, done) => {
-  setTimeout(done, 100);
+  setTimeout(() => {
+    // Empty timer so the process doesn't exit before the timeout triggers.
+  }, 5);
+  setTimeout(done, 30_000_000).unref();
 });