fix(repository): Move backend code into subdirectory

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

backend/src/history/history.module.ts

@@ -0,0 +1,27 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { Module } from '@nestjs/common';
+import { ConfigModule } from '@nestjs/config';
+import { TypeOrmModule } from '@nestjs/typeorm';
+
+import { LoggerModule } from '../logger/logger.module';
+import { NotesModule } from '../notes/notes.module';
+import { UsersModule } from '../users/users.module';
+import { HistoryEntry } from './history-entry.entity';
+import { HistoryService } from './history.service';
+
+@Module({
+  providers: [HistoryService],
+  exports: [HistoryService],
+  imports: [
+    LoggerModule,
+    TypeOrmModule.forFeature([HistoryEntry]),
+    UsersModule,
+    NotesModule,
+    ConfigModule,
+  ],
+})
+export class HistoryModule {}