Remove unnecessary conversion

`GetAbsolutePathToOutputFile` returns a `std::string` and `OpenFileForWriting`
takes a `std::string&`.

PiperOrigin-RevId: 589984409
Change-Id: I75be9cb105f49b3a279a5d33b1b82dfcfc912cfd
diff --git a/googletest/src/gtest.cc b/googletest/src/gtest.cc
index 85d45b5..479b2ee 100644
--- a/googletest/src/gtest.cc
+++ b/googletest/src/gtest.cc
@@ -6203,8 +6203,8 @@
 #if GTEST_HAS_FILE_SYSTEM
   const std::string& output_format = UnitTestOptions::GetOutputFormat();
   if (output_format == "xml" || output_format == "json") {
-    FILE* fileout = OpenFileForWriting(
-        UnitTestOptions::GetAbsolutePathToOutputFile().c_str());
+    FILE* fileout =
+        OpenFileForWriting(UnitTestOptions::GetAbsolutePathToOutputFile());
     std::stringstream stream;
     if (output_format == "xml") {
       XmlUnitTestResultPrinter(