Enable deletion of relation fields (#5338)

In this PR
1. Enable deletion of relation fields in the product and via the api
(migration part was missing in the api)
3. Change wording, only use "deactivate" and "delete" everywhere (and
not a mix of the two + "disable", "erase")

packages/twenty-front/src/pages/settings/data-model/SettingsObjectEdit.tsx

@@ -146,10 +146,10 @@ export const SettingsObjectEdit = () => {
             />
           </Section>
           <Section>
-            <H2Title title="Danger zone" description="Disable object" />
+            <H2Title title="Danger zone" description="Deactivate object" />
             <Button
               Icon={IconArchive}
-              title="Disable"
+              title="Deactivate"
               size="small"
               onClick={handleDisable}
             />