More specific and unique feed name for NuGet install command template. (#23889)

The default command to setup a NuGet registry from the command line is:
```
dotnet nuget add source --name Gitea --username your_username --password your_token <gitea-origin-url/>
```
The feed name `Gitea` is hard-coded into the command template, so each
registry will by default have the same feed name. I know templates can
be overridden using the `custom` folder. But in my opinion, it's a good
practice to make a slight change in the default template to make the
feed name more context specific:
```
dotnet nuget add source --name {{.PackageDescriptor.Owner.Name}} --username your_username --password your_token <gitea-origin-url/>
```

Author: bvandevliet

templates/package/content/nuget.tmpl

@@ -4,11 +4,11 @@
 		<div class="ui form">
 			<div class="field">
 				<label>{{svg "octicon-terminal"}} {{.locale.Tr "packages.nuget.registry"}}</label>
-				<div class="markup"><pre class="code-block"><code>dotnet nuget add source --name Gitea --username your_username --password your_token <gitea-origin-url data-url="{{AppSubUrl}}/api/packages/{{.PackageDescriptor.Owner.Name}}/nuget/index.json"></gitea-origin-url></code></pre></div>
+				<div class="markup"><pre class="code-block"><code>dotnet nuget add source --name {{.PackageDescriptor.Owner.Name}} --username your_username --password your_token <gitea-origin-url data-url="{{AppSubUrl}}/api/packages/{{.PackageDescriptor.Owner.Name}}/nuget/index.json"></gitea-origin-url></code></pre></div>
 			</div>
 			<div class="field">
 				<label>{{svg "octicon-terminal"}} {{.locale.Tr "packages.nuget.install"}}</label>
-				<div class="markup"><pre class="code-block"><code>dotnet add package --source Gitea --version {{.PackageDescriptor.Version.Version}} {{.PackageDescriptor.Package.Name}}</code></pre></div>
+				<div class="markup"><pre class="code-block"><code>dotnet add package --source {{.PackageDescriptor.Owner.Name}} --version {{.PackageDescriptor.Version.Version}} {{.PackageDescriptor.Package.Name}}</code></pre></div>
 			</div>
 			<div class="field">
 				<label>{{.locale.Tr "packages.nuget.documentation" | Safe}}</label>