4002 prevent user from creating twice the same blocklist item (#5213)

Closes #4002

packages/twenty-server/src/modules/connected-account/repositories/blocklist.repository.ts

@@ -50,4 +50,21 @@ export class BlocklistRepository {
       transactionManager,
     );
   }
+
+  public async getByWorkspaceMemberIdAndHandle(
+    workspaceMemberId: string,
+    handle: string,
+    workspaceId: string,
+    transactionManager?: EntityManager,
+  ): Promise<ObjectRecord<BlocklistObjectMetadata>[]> {
+    const dataSourceSchema =
+      this.workspaceDataSourceService.getSchemaName(workspaceId);
+
+    return await this.workspaceDataSourceService.executeRawQuery(
+      `SELECT * FROM ${dataSourceSchema}."blocklist" WHERE "workspaceMemberId" = $1 AND "handle" = $2`,
+      [workspaceMemberId, handle],
+      workspaceId,
+      transactionManager,
+    );
+  }
 }