feat: 新增軟體包管理器子主題

Signed-off-by: 林博仁(Buo-ren Lin) <[email protected]>

.gitmodules

@@ -7,3 +7,7 @@
 #
 # Copyright 2024 林博仁(Buo-ren Lin) <[email protected]>
 # SPDX-License-Identifier: CC-BY-SA-4.0
+[submodule "軟體包管理器 Package managers"]
+	path = 軟體包管理器 Package managers
+	url = https://gitlab.com/libre-knowledge/package-managers.git
+	ignore = true

README.md

@@ -5,6 +5,13 @@
 <https://gitlab.com/libre-knowledge/software-distribution>  
 [![GitLab CI 持續整合流程狀態標章](https://gitlab.com/libre-knowledge/software-distribution/badges/main/pipeline.svg?ignore_skipped=true "點擊查看 GitLab CI 持續整合流程的運行狀態")](https://gitlab.com/libre-knowledge/software-distribution/-/commits/main) [![「檢查專案中的潛在問題」GitHub Actions 作業流程狀態標章](https://github.com/libre-knowledge/software-distribution/actions/workflows/check-potential-problems.yml/badge.svg "本專案使用 GitHub Actions 自動化檢查專案中的潛在問題")](https://github.com/libre-knowledge/software-distribution/actions/workflows/check-potential-problems.yml) [![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white "本專案使用 pre-commit 檢查專案中的潛在問題")](https://github.com/pre-commit/pre-commit) [![REUSE 規範遵從狀態標章](https://api.reuse.software/badge/gitlab.com/libre-knowledge/software-distribution "本專案遵從 REUSE 規範降低軟體授權合規成本")](https://api.reuse.software/info/gitlab.com/libre-knowledge/software-distribution)
 
+## 子主題
+
+以下列舉本主題相關的主題：
+
+* [軟體包管理器<br>Package managers](https://gitlab.com/libre-knowledge/package-managers)  
+  自動化安裝、升級、設定與移除電腦軟體流程的軟體集合
+
 ## 參考資料
 
 以下列舉撰寫本主題內容時所參考的第三方資源：