Now that fmt plays nice with gcc let's actually use it: replace std::to_string, boost lexical_cast and a couple miscellaneous llformats with fmt. (Alchemy sync-ish)

indra/llcommon/CMakeLists.txt

@@ -299,6 +299,7 @@ target_link_libraries(
     ${Boost_SYSTEM_LIBRARY}
     ${CORESERVICES_LIBRARY}
     ${URIPARSER_LIBRARY}
+    fmt::fmt
     nlohmann_json::nlohmann_json
     absl::strings
     ${RT_LIBRARY}