Remove three old env variables (#2297)

* remove three old env variables IS_DATA_MODEL_SETTINGS_ENABLED IS_DEVELOPERS_SETTINGS_ENABLED FLEXIBLE_BACKEND_ENABLED

* Fix database:reset script

* Removing unused variable

---------

Co-authored-by: Charles Bochet <charles@twenty.com>

front/src/modules/client-config/states/isDataModelSettingsEnabled.ts

@@ -1,6 +0,0 @@
-import { atom } from 'recoil';
-
-export const isDataModelSettingsEnabledState = atom<boolean>({
-  key: 'isDataModelSettingsEnabledState',
-  default: false,
-});

front/src/modules/client-config/states/isDevelopersSettingsEnabled.ts

@@ -1,6 +0,0 @@
-import { atom } from 'recoil';
-
-export const isDevelopersSettingsEnabledState = atom<boolean>({
-  key: 'isDevelopersSettingsEnabledState',
-  default: false,
-});

front/src/modules/client-config/states/isFlexibleBackendEnabledState.ts

@@ -1,6 +0,0 @@
-import { atom } from 'recoil';
-
-export const isFlexibleBackendEnabledState = atom<boolean>({
-  key: 'isFlexibleBackendEnabledState',
-  default: false,
-});