Enable markdownlint `no-trailing-punctuation` and `no-blanks-blockquote` (#29214)

Enable these two and fix issues.

.markdownlint.yaml

@@ -5,13 +5,11 @@ heading-increment: false
 line-length: {code_blocks: false, tables: false, stern: true, line_length: -1}
 no-alt-text: false
 no-bare-urls: false
-no-blanks-blockquote: false
 no-emphasis-as-heading: false
 no-empty-links: false
 no-hard-tabs: {code_blocks: false}
 no-inline-html: false
 no-space-in-code: false
 no-space-in-emphasis: false
-no-trailing-punctuation: false
 no-trailing-spaces: {br_spaces: 0}
 single-h1: false

docs/content/administration/customizing-gitea.en-us.md

@@ -284,7 +284,7 @@ syntax and shouldn't be touched without fully understanding these components.
 
 Google Analytics, Matomo (previously Piwik), and other analytics services can be added to Gitea. To add the tracking code, refer to the `Other additions to the page` section of this document, and add the JavaScript to the `$GITEA_CUSTOM/templates/custom/header.tmpl` file.
 
-## Customizing gitignores, labels, licenses, locales, and readmes.
+## Customizing gitignores, labels, licenses, locales, and readmes
 
 Place custom files in corresponding sub-folder under `custom/options`.
 

docs/content/administration/mail-templates.en-us.md

@@ -222,7 +222,7 @@ Please check [Gitea's logs](administration/logging-config.md) for error messages
         <a href="{{.Link}}">{{.Repo}}#{{.Issue.Index}}</a>.
         </p>
         {{if not (eq .Body "")}}
-            <h3>Message content:</h3>
+            <h3>Message content</h3>
             <hr>
             {{.Body | Str2html}}
         {{end}}
@@ -245,7 +245,7 @@ This template produces something along these lines:
 
 > [@rhonda](#) (Rhonda Myers) updated [mike/stuff#38](#).
 >
-> #### Message content:
+> #### Message content
 >
 > \_********************************\_********************************
 >

docs/content/administration/mail-templates.zh-cn.md

@@ -228,7 +228,7 @@ _主题_ 和 _邮件正文_ 由 [Golang的模板引擎](https://go.dev/pkg/text/
 
 > [@rhonda](#)（Rhonda Myers）更新了 [mike/stuff#38](#)。
 >
-> #### 消息内容：
+> #### 消息内容
 >
 > \_********************************\_********************************
 >

docs/content/contributing/guidelines-frontend.en-us.md

@@ -34,7 +34,7 @@ The source files can be found in the following directories:
 
 We recommend [Google HTML/CSS Style Guide](https://google.github.io/styleguide/htmlcssguide.html) and [Google JavaScript Style Guide](https://google.github.io/styleguide/jsguide.html)
 
-### Gitea specific guidelines:
+### Gitea specific guidelines
 
 1. Every feature (Fomantic-UI/jQuery module) should be put in separate files/directories.
 2. HTML ids and classes should use kebab-case, it's preferred to contain 2-3 feature related keywords.

docs/content/contributing/guidelines-frontend.zh-cn.md

@@ -34,7 +34,7 @@ HTML 页面由[Go HTML Template](https://pkg.go.dev/html/template)渲染。
 
 我们推荐使用[Google HTML/CSS Style Guide](https://google.github.io/styleguide/htmlcssguide.html)和[Google JavaScript Style Guide](https://google.github.io/styleguide/jsguide.html)。
 
-## Gitea 特定准则：
+## Gitea 特定准则
 
 1. 每个功能（Fomantic-UI/jQuery 模块）应放在单独的文件/目录中。
 2. HTML 的 id 和 class 应使用 kebab-case，最好包含2-3个与功能相关的关键词。

docs/content/development/api-usage.zh-cn.md

@@ -60,7 +60,7 @@ curl "http://localhost:4000/api/v1/repos/test1/test1/issues" \
 `/users/:name/tokens` 是一个特殊的接口，需要您使用 basic authentication 进行认证，具体原因在 issue 中
 [#3842](https://github.com/go-gitea/gitea/issues/3842#issuecomment-397743346) 有所提及，使用方法如下所示：
 
-### 使用 Basic authentication 认证：
+### 使用 Basic authentication 认证
 
 ```
 $ curl --url https://yourusername:yourpassword@gitea.your.host/api/v1/users/yourusername/tokens