releases: add tidb 5.0.5 release notes (#7062)

TOC.md

@@ -564,6 +564,7 @@
     - [5.1.1](/releases/release-5.1.1.md)
     - [5.1.0](/releases/release-5.1.0.md)
   - v5.0
+    - [5.0.5](/releases/release-5.0.5.md)
     - [5.0.4](/releases/release-5.0.4.md)
     - [5.0.3](/releases/release-5.0.3.md)
     - [5.0.2](/releases/release-5.0.2.md)

releases/release-5.0.5.md

@@ -0,0 +1,21 @@
+---
+title: TiDB 5.0.5 Release Notes
+---
+
+# TiDB 5.0.5 Release Notes
+
+Release date: December 3, 2021
+
+TiDB version: 5.0.5
+
+## Improvement
+
++ TiDB
+
+    - Upgrade the Grafana version from 7.5.7 to 7.5.11
+
+## Bug fix
+
++ TiKV
+
+    - Fix the issue that the `GcKeys` task does not work when it is called by multiple keys. Caused by this issue, compaction filer GC might not drop the MVCC deletion information. [#11217](https://github.com/tikv/tikv/issues/11217)

releases/release-notes.md

@@ -19,6 +19,7 @@ title: Release Notes
 
 ## 5.0
 
+- [5.0.5](/releases/release-5.0.5.md)
 - [5.0.4](/releases/release-5.0.4.md)
 - [5.0.3](/releases/release-5.0.3.md)
 - [5.0.2](/releases/release-5.0.2.md)

releases/release-timeline.md

@@ -9,6 +9,7 @@ This document shows all the released TiDB versions in reverse chronological orde
 
 | Version | Release Date |
 | :--- | :--- |
+| [5.0.5](/releases/release-5.0.5.md) | 2021-12-03 |
 | [5.2.3](/releases/release-5.2.3.md) | 2021-12-03 |
 | [5.3.0](https://docs.pingcap.com/tidb/v5.3/release-5.3.0) | 2021-11-30 |
 | [5.2.2](/releases/release-5.2.2.md) | 2021-10-29 |