Fix memory leak in LiftWriter (#1484)

* Dispose temporary XML readers in LiftWriter

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: jasonleenaylor <[email protected]>

Author: Copilot

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - [SIL.Core.Clearshare] New tests MetadataBareTests are based on previous MetadataTests in SIL.Windows.Forms.Clearshare. The tests were updated to use ImageSharp instead of Winforms for handling images.
 
 ### Fixed
+- [SIL.DictionaryServices] Fix memory leak in LiftWriter
 - [SIL.WritingSystems] Fix IetfLanguageTag.GetGeneralCode to handle cases when zh-CN or zh-TW is a prefix and not the whole string.
 - [SIL.Windows.Forms] Prevent BetterLabel from responding to OnTextChanged when it has been disposed.
 - [SIL.Windows.Forms] Prevent ContributorsListControl.GetContributionFromRow from throwing an exception when the DataGridView has no valid rows selected.

SIL.DictionaryServices/Lift/LiftWriter.cs

@@ -726,19 +726,21 @@ protected void WriteLanguageFormsInWrapper(IEnumerable<LanguageForm> forms, stri
 
 				string scaryUnicodeEscaped = form.Form.EscapeAnyUnicodeCharactersIllegalInXml();
 				string safeFromScaryUnicodeSoItStaysEscaped = scaryUnicodeEscaped.Replace("&#x", "");
-				XmlReader testerForWellFormedness = XmlReader.Create(new StringReader("<temp>" + safeFromScaryUnicodeSoItStaysEscaped + "</temp>"));
-
 				bool isTextWellFormedXml = true;
-				try
+				using (var stringReader = new StringReader("<temp>" + safeFromScaryUnicodeSoItStaysEscaped + "</temp>"))
+				using (var testerForWellFormedness = XmlReader.Create(stringReader))
 				{
-					while (testerForWellFormedness.Read())
+					try
 					{
-						//Just checking for well formed XML
+						while (testerForWellFormedness.Read())
+						{
+							//Just checking for well formed XML
+						}
+					}
+					catch
+					{
+						isTextWellFormedXml = false;
 					}
-				}
-				catch
-				{
-					isTextWellFormedXml = false;
 				}
 
 				if (isTextWellFormedXml)