Add language slugs (System.Xml)

[gewarren]

Prep for dotnet/docs#45892.

(Hide whitespace changes.)

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/area-system-xml

[learn-build-service-prod]

Learn Build status updates of commit a4fca9d:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Xml.Linq/XAttribute.xml	✅Succeeded	View
xml/System.Xml.Linq/XDocument.xml	✅Succeeded	View
xml/System.Xml.Linq/XElement.xml	✅Succeeded	View
xml/System.Xml.Linq/XName.xml	✅Succeeded	View
xml/System.Xml.Linq/XNamespace.xml	✅Succeeded	View
xml/System.Xml.Linq/XProcessingInstruction.xml	✅Succeeded	View
xml/System.Xml.Linq/XStreamingElement.xml	✅Succeeded	View
xml/System.Xml.Schema/XmlSchemaCollection.xml	✅Succeeded	View
xml/System.Xml.Schema/XmlSchemaSet.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlAttributeEventArgs.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlAttributes.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlSerializer.xml	✅Succeeded	View
xml/System.Xml.XPath/XPathNavigator.xml	✅Succeeded	View
xml/System.Xml.Xsl/XslTransform.xml	✅Succeeded	View
xml/System.Xml/XmlDictionaryWriter.xml	✅Succeeded	View
xml/System.Xml/XmlDocument.xml	✅Succeeded	View
xml/System.Xml/XmlNamespaceManager.xml	✅Succeeded	View
xml/System.Xml/XmlNode.xml	✅Succeeded	View
xml/System.Xml/XmlReader.xml	✅Succeeded	View
xml/System.Xml/XmlReaderSettings.xml	✅Succeeded	View
xml/System.Xml/XmlTextReader.xml	✅Succeeded	View
xml/System.Xml/XmlWriter.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

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[BillWagner]

This LGTM @gewarren

I had a few comments where the output was XML. I wasn't sure if the best choice was txt or xml. I only did that with blocks where the output was a valid XML doc, not where the output include XML and other text.

[learn-build-service-prod]

Learn Build status updates of commit cb8853c:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Xml.Linq/XAttribute.xml	✅Succeeded	View
xml/System.Xml.Linq/XDocument.xml	✅Succeeded	View
xml/System.Xml.Linq/XElement.xml	✅Succeeded	View
xml/System.Xml.Linq/XName.xml	✅Succeeded	View
xml/System.Xml.Linq/XNamespace.xml	✅Succeeded	View
xml/System.Xml.Linq/XProcessingInstruction.xml	✅Succeeded	View
xml/System.Xml.Linq/XStreamingElement.xml	✅Succeeded	View
xml/System.Xml.Schema/XmlSchemaCollection.xml	✅Succeeded	View
xml/System.Xml.Schema/XmlSchemaSet.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlAttributeEventArgs.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlAttributes.xml	✅Succeeded	View
xml/System.Xml.Serialization/XmlSerializer.xml	✅Succeeded	View
xml/System.Xml.XPath/XPathNavigator.xml	✅Succeeded	View
xml/System.Xml.Xsl/XslTransform.xml	✅Succeeded	View
xml/System.Xml/XmlDictionaryWriter.xml	✅Succeeded	View
xml/System.Xml/XmlDocument.xml	✅Succeeded	View
xml/System.Xml/XmlNamespaceManager.xml	✅Succeeded	View
xml/System.Xml/XmlNode.xml	✅Succeeded	View
xml/System.Xml/XmlReader.xml	✅Succeeded	View
xml/System.Xml/XmlReaderSettings.xml	✅Succeeded	View
xml/System.Xml/XmlTextReader.xml	✅Succeeded	View
xml/System.Xml/XmlWriter.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel