Remove block which is not used

[podarok]

Original Issue, this PR is going to fix: #1928 + https://openy.atlassian.net/browse/MAINTAIN-20

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[gundevel]

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[gundevel]

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[hamrant]

In this case we can remove everything related to this:

$this->schedule = $schedule;
return $this->schedule;

just return $schedule;

And remove

  /**
   * Cached schedule.
   *
   * @var array
   */
  private $schedule = [];

[gundevel]

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[gundevel]

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[gundevel]

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[gundevel]

Open Y Upgrade Path site check installed at http://upgrade.openy.cibox.tools/build3206/