fix formatting and use context.page_title

Author: Mpdreamz

docs/syntax/_snippets/reusable-snippet.md

@@ -1,4 +1,4 @@
-This is a snippet included on "{{page_title}}".
+This is a snippet included on "{{context.page_title}}".
 
 :::{tip}
 This is a snippet

docs/testing/nested/index.md

@@ -1,8 +1,9 @@
 ---
 sub:
   x: "Variable"
+navigation_title: "Testing nesting and {{x}}"
 ---
-# Testing Nesting
+# Testing Nesting and {{x}}
 
 The files in this directory are used for testing purposes. Do not edit these files unless you are working on tests.
 

src/Elastic.Markdown/Helpers/Interpolation.cs

@@ -54,7 +54,7 @@ public static bool ReplaceSubstitutions(
 	public static bool ReplaceSubstitutions(
 		this ReadOnlySpan<char> span,
 		IReadOnlyDictionary<string, string>[] properties,
-		[NotNullWhen(true)]out string? replacement
+		[NotNullWhen(true)] out string? replacement
 	)
 	{
 		replacement = null;