API Made the GridFieldDeleteAction method getRemoveAction() protected

[mooror]

Description

I expected to be able to subclass the GridFieldDeleteAction and alter the underlying GridField_FormAction without having to completely overwrite parent code

I found that the getRemoveAction() method is private and has no extension points making it impossible to change the GridField_FormAction while keeping existing parent code

I have changed the access modifier for getRemoveAction() from private to protected to fix this issue

Manual testing steps

Issues

• Make the form action in GridFieldDeleteAction extensible #11368

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[GuySartorelli]

LGTM, nice an simple. Thanks.

[mooror]

Epic! Thanks Guy 🎊