Update dependency flutter_slidable to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
flutter_slidable	dependencies	major	^3.0.0 → 4.0.3

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Warning

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Release Notes

letsar/flutter_slidable (flutter_slidable)

v4.0.3

Fixed

• Fixes issue with dismissal #​537

v4.0.2

Fixed

• Issue when actionPaneConfigurator is null when calling openCurrentActionPane. Thanks to @​EM-Sabeel.

v4.0.1

Fixed

• Issue in auto_close_behavior where removeStatusListener was not called.

v4.0.0

Changed

• Minimum version of Flutter (3.27.0 now)

Fixed

• Icon color in actions #​512
• Use withValues instead of withOpacity

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