Updated PropertySummaryDocumentationAnalyzer to prepare for the correct code fix for a public property with a private getter and summary which starts with "Gets".

Author: bjornhellander

StyleCop.Analyzers/StyleCop.Analyzers.Test/DocumentationRules/SA1623UnitTests.cs

@@ -199,6 +199,7 @@ public int Property
         [InlineData("public", "int", "{ set {} }", "Gets", "Sets")] // Regression test for #2253
         [InlineData("public", "int", "{ set {} }", "Gets or sets", "Sets")] // Regression test for #2253
         [InlineData("public", "int", "{ get; private set; }", "Sets", "Gets")] // Regression test for #2253
+        [InlineData("public", "int", "{ private get; set; }", "Gets", "Sets")] // Regression test for #2253
         public async Task IncorrectSummaryTagWithKnownPrefixShouldBeFixedCorrectlyAsync(string accessibility, string type, string accessors, string summaryPrefix, string expectedArgument)
         {
             var testCode = $@"

StyleCop.Analyzers/StyleCop.Analyzers/DocumentationRules/PropertySummaryDocumentationAnalyzer.cs

@@ -305,6 +305,12 @@ private static void AnalyzeSummaryElement(SyntaxNodeAnalysisContext context, Xml
                         else
                         {
                             diagnosticProperties.Add(ExpectedTextKey, startingTextSets);
+
+                            if (prefixIsGets)
+                            {
+                                diagnosticProperties.Add(TextToRemoveKey, text.Substring(0, startingTextGets.Length));
+                            }
+
                             context.ReportDiagnostic(Diagnostic.Create(SA1623Descriptor, diagnosticLocation, diagnosticProperties.ToImmutable(), startingTextSets));
                         }
                     }