treewide: Convert most fmt::format -> std::format

Change-Id: I3c9ac1eed1c86c6cd9f7fd3a1ba356734e79f937
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/test/test_config_parser.cpp b/test/test_config_parser.cpp
index d666502..692cabd 100644
--- a/test/test_config_parser.cpp
+++ b/test/test_config_parser.cpp
@@ -8,6 +8,7 @@
 #include <xyz/openbmc_project/Common/error.hpp>
 
 #include <exception>
+#include <format>
 #include <fstream>
 #include <stdexcept>
 
@@ -76,7 +77,7 @@
 class TestConfigParser : public stdplus::gtest::TestWithTmp
 {
   public:
-    std::string filename = fmt::format("{}/eth0.network", CaseTmpDir());
+    std::string filename = std::format("{}/eth0.network", CaseTmpDir());
     Parser parser;
 
     void WriteSampleFile()
@@ -180,7 +181,7 @@
 TEST_F(TestConfigParser, Perf)
 {
     GTEST_SKIP();
-    stdplus::fd::AtomicWriter file(fmt::format("{}/tmp.XXXXXX", CaseTmpDir()),
+    stdplus::fd::AtomicWriter file(std::format("{}/tmp.XXXXXX", CaseTmpDir()),
                                    0600);
     stdplus::fd::FormatBuffer out(file);
     std::string obj(500, 'a');