PHPstan job was failed

Problem/Motivation

The phpstan job failed.

Line footable.module
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51 Call to deprecated function template_preprocess_views_view_table():
in drupal:11.3.0 and is removed from drupal:12.0.0. Initial
template_preprocess functions are registered directly in hook_theme().
99 Variable $field_handler in empty() always exists and is not falsy.
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Line src/Entity/FooTableBreakpoint.php
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102 Call to an undefined method Drupal\Core\Config\Entity\ConfigEntityInterface::getBreakpoint().
103 Call to an undefined method Drupal\Core\Config\Entity\ConfigEntityInterface::getBreakpoint().
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Line src/FooTable.php
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56 Call to an undefined method Drupal\Core\Entity\EntityInterface::getBreakpoint().
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Line src/FooTableBreakpointListBuilder.php
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31 Call to an undefined method Drupal\Core\Entity\EntityInterface::getBreakpoint().
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Line src/Form/FooTableBreakpointForm.php
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46 Call to an undefined method Drupal\Core\Entity\EntityInterface::getBreakpoint().
72 Method Drupal\footable\Form\FooTableBreakpointForm::save() should return int but return statement is missing.
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[ERROR] Found 8 errors

Steps to reproduce

Go to the https://git.drupalcode.org/issue/footable-3586300/-/jobs/9510357
Check parent issue - (see here https://www.drupal.org/project/footable/issues/3586300).

Proposed resolution

Replace the deprecated function.
Add a return statement.

Remaining tasks

None.

User interface changes

None.

API changes

None.

Data model changes

None.