Fix issues with getters returning collection types.

[SilasKenneth]

Summary

The getters for collection type properties are never creating the class objects in the right way. For instance, having the following data,

  ...
   "attendees": [
      {"email": "attendee1@example.com"},
      {"email": "attendee2@example.com"},
      {"email": "attendee3@example.com"}
   ]
  ...

the getters create one object passing the array of JSON objects as an argument.

Current behaviour.

   ...
   $this->_propDict['attendees'] = new Attendee($this->_propDict['attendees']);
   ...

Expected behaviour.

Instead, we would like to create an instance of Attendee for each attendee as follows,

 ...
  $attendees = [];
  foreach($this->_propDict['attendees'] as $attendee){
     $attendees[] = new Attendee($attendee);
  }
  $this->_propDict['attendees'] = $attendees;
 ...

Generated code differences

Command line arguments to run these changes

Provide the command line arguments here so that reviewers can quickly repro the results of changes.

Links to issues or work items this PR addresses

Fixes #496
Fixes #87
Fixes #97
Fixes #115
Fixes #222
Fixes #76
Closes #523

Microsoft Reviewers: Open in CodeFlow

[Ndiritu]

Perhaps something to think about in Kiota...
Should a getter be modifying/setting the value of a property? Maybe this logic should be handled within the constructor?/somewhere else during object creation/deserialization?

[MIchaelMainer]

We will want to batch these breaking changes with other breaking changes. We will need to capture information in an upgrade guide as customers will have taken a dependency on the previous broken behavior by implementing a workaround.

[Ndiritu]

Changed the base branch of this PR to support/php-2.x.x which will contain all breaking changes and finally be merged to dev when v2 is stable