Remove usage of g++-13 libstdc++ <format> (#130)

* Remove usage of C++20 <format> for backwards compatibility w/ GNU
toolchains 11/12

* Remove unused import of <format> in Meter

Author: vardaro

libs/meter/meter_id/meter_id.cpp

@@ -1,7 +1,6 @@
 #include <meter_id.h>
 
 #include <util.h>
-#include <format>
 #include <sstream>
 
 // Define the static member

libs/writer/writer_wrapper/test_writer.cpp

@@ -4,7 +4,7 @@
 #include <writer_test_helper.h>
 
 #include <gtest/gtest.h>
-#include <format>
+#include <fmt/core.h>
 #include <iostream>
 #include <thread>
 #include <chrono>
@@ -70,7 +70,7 @@ TEST_F(WriterWrapperUDSWriterTest, MultithreadedWrite)
         // Create several counters per thread with unique names
         for (int i = 0; i < countersPerThread; i++)
         {
-            std::string counterName = std::format("counter.thread{}.{}", threadId, i);
+            std::string counterName = fmt::format("counter.thread{}.{}", threadId, i);
             MeterId meterId(counterName);
             Counter counter(meterId);
 
@@ -123,4 +123,4 @@ TEST_F(WriterWrapperUDSWriterTest, MultithreadedWrite)
     }
 
     EXPECT_EQ(actualIncrements, expectedIncrements);
-}
+}