fix: new method to check if received all suite results

[wlldrygla]

I fixed issue #4416, creating a new method: GlobalReporter.waitResultForAllSuites

What I did was:

1. On the DefaultRunner.runConcurrent, I count the modules where are running (test suites/files)
2. Pass this number to DefaultRunner.reportResults
3. DefaultRunner.reportResults call GlobalReporter.waitResultForAllSuites if received totalSuitesExpected
4. GlobalReporter.waitResultForAllSuites checks if GlobalReporter.totalSuites length is equal to totalSuitesExpected
   4.1 if is different, checks each 500ms again, to check if a result arrived and the GlobalReporter.totalSuites length is equal to totalSuitesExpected
   4.2 I added a timeout of 30s to this, to await results arrive
5. When condition is met or timeouts, the flow keep going and call the GlobalReporter.create with available suites results

I tested this during several days, never had a missing result, but, I had logs to prove that would have missing results, I will let them bellow, but, what I saw was, GlobalReporter.addTestSuiteResults been call (triggered by the event emited on worker-task) while GlobalReporter.save was already running (and it uses the GlobalReporter.globalResults builded before, so the new suite result isnt used to generate files).
I also tested running tests alone, without use DefaultRunner.runConcurrent and it keep working as expected

NORMAL CASE:

[global-reports.js] GlobalReporter.save - starting
[global-reports.js] GlobalReporter.save - expected suites: 77
[global-reports.js] GlobalReporter.save - total suites until now: 77
[global-reports.js] GlobalReporter.waitResultForAllSuites - if to check suites total
[global-reports.js] GlobalReporter.waitResultForAllSuites - condition met 77  =  77
[global-reports.js] GlobalReporter.save - RETURN
 Wrote HTML report file to: NIGHTWATCH-REPO-PATH/reports/nightwatch-html-report/index.html

RESULT ARRIVING WHILE SAVE RUNNING

[global-reports.js] GlobalReporter.save - starting
[global-reports.js] GlobalReporter.save - expected suites: 77
[global-reports.js] GlobalReporter.save - total suites results until now: 76
[global-reports.js] GlobalReporter.waitResultForAllSuites - inside if to check suites total
[global-reports.js] GlobalReporter.waitResultForAllSuites - condition NOT met 76  !=  77
[worker-task.js] WorkerTask.runWorkerTask: port2.onmessage “testsuite_finished” for suite: chrome: 
tests/TESTCASE_NAME_77.ts
[global-reports.js] GlobalReporter.setupChildProcessListener: on message, suitename: chrome: tests/TESTCASE_NAME_77.ts
[global-reports.js] GlobalReporter.addTestSuiteResults start
[global-reports.js] GlobalReporter.addTestSuiteResults - new total suites:  77
[global-reports.js] GlobalReporter.waitResultForAllSuites - condition met 77  =  77
[global-reports.js] GlobalReporter.save - RETURN
 Wrote HTML report file to: NIGHTWATCH-REPO-PATH/reports/nightwatch-html-report/index.html

_ I omitted file names because I runned using a private repository_

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