Fix multi select filtering (#5358) (#8452)

Allow filtering by multi-select fields.

<img width="1053" alt="Screenshot 2024-11-11 at 11 54 45"
src="https://github.com/user-attachments/assets/a79b2251-94e3-48f8-abda-e808103a6c39">

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Co-authored-by: Félix Malfait <felix@twenty.com>

packages/twenty-server/src/engine/api/graphql/workspace-schema-builder/utils/generate-fields.utils.ts

@@ -58,7 +58,9 @@ export const generateFields = <
       ? {
           nullable: fieldMetadata.isNullable,
           defaultValue: fieldMetadata.defaultValue,
-          isArray: fieldMetadata.type === FieldMetadataType.MULTI_SELECT,
+          isArray:
+            kind !== InputTypeDefinitionKind.Filter &&
+            fieldMetadata.type === FieldMetadataType.MULTI_SELECT,
           settings: fieldMetadata.settings,
           isIdField: fieldMetadata.name === 'id',
         }