remove old feature toggles

[adamwhitlock1]

Summary

• removes 4 feature toggles that are being removed from the FE via this PR: Profile/aw/53357/feature toggle removal cleanup vets-website#23475

profile_schema_forms
profile_show_address_change_modal
profile_use_security_process_list
profile_block_for_fiduciary_deceased_or_incompetent

Related issue(s)

• [FE] Review feature flipper for accessibility feature flags that can be removed va.gov-team#53357

Testing done

• Verified that application works as expected with toggles removed
• FE tests updated that relied on flags

What areas of the site does it impact?

Profile application

Acceptance criteria

• Toggles removed
• I fixed|updated|added unit tests and integration tests for each feature (if applicable).