fix: ensure option 'selected' key is set in AttributeGroupFrontendView

The commit makes a precautionary check and sets the value of the 'selected' key of the 'option' array as false, if not previously set in the AttributeGroupFrontendView.php. This prevents potential undefined index errors on subsequent checks using this key.

mentioned in commit 8ffb7d18

merged

This MR is included in version 2.5.3

The release is available on GitLab release.

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