chore!: remove old deprecations

[justlevine]

What

Removes deprecated GraphQL fields, WP hooks, and util methods.

Why

Tech debt

How

• chore!: Remove deprecated fields from the schema: FormsConnectionOrderbyInput.field, GfFieldWithDisableQuantitySetting.isQuantityDisabled. GfSubmittedEntry.entryId. GfForm.button, gfForm.entryId, gfForm.lastPageButton.
• chore!: Remove deprecated hooks: graphql_gf_form_modeled_data_experimental, graphql_gf_form_field_setting_properties, graphql_gf_form_field_value_properties.
• chore!: Remove deprecated helper method: GFUtils::handle_file_upload().

Testing Instructions

Additional Info

Checklist:

• [x] This PR is tested to the best of my abilities.
• [x] This PR follows the WordPress Coding Standards.
• [x] This PR has proper inline documentation.
• [x] This PR has unit tests to verify the code works as intended.
• [x] The changes in this PR have been noted in CHANGELOG.md