Add note that Uri.Query and Fragment include the leading delimiter (#8977)

Author: MihaZupan

xml/System/Uri.xml

@@ -2173,7 +2173,7 @@ If you used an escaped string to construct this instance (for example, `"http://
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets the escaped URI fragment.</summary>
+        <summary>Gets the escaped URI fragment, including the leading '#' character if not empty.</summary>
         <value>URI fragment information.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[
@@ -4241,7 +4241,7 @@ If you used an escaped string to construct this instance (for example, `"http://
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets any query information included in the specified URI.</summary>
+        <summary>Gets any query information included in the specified URI, including the leading '?' character if not empty.</summary>
         <value>Any query information included in the specified URI.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[

xml/System/UriBuilder.xml

@@ -657,7 +657,7 @@ Note: In <see href="https://docs.microsoft.com/previous-versions/br230232(v=vs.1
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets or sets the fragment portion of the URI.</summary>
+        <summary>Gets or sets the fragment portion of the URI, including the leading '#' character if not empty.</summary>
         <value>The fragment portion of the URI.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[  
@@ -1017,7 +1017,7 @@ The <xref:System.UriBuilder.Fragment> property contains any text following a fra
         <ReturnType>System.String</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>Gets or sets any query information included in the URI.</summary>
+        <summary>Gets or sets any query information included in the URI, including the leading '?' character if not empty.</summary>
         <value>The query information included in the URI.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[