[WIP] changes for next release 3.10.2

[nlohmann]

This thread collects all changes made since the 3.10.1 (#2971) release.

Further Changes

• Fix tag for release.
  • 3.10.1 zip json.hpp has version number 3.10.0 instead of 3.10.1 #2973
• Fix -Wunused warnings on JSON_DIAGNOSTICS. By @gcerretani.
  • Annoying -Wundef on new JSON_DIAGNOSTICS macro #2975
  • Fix -Wunused warnings on JSON_DIAGNOSTICS  #2976

[nlohmann]

Release: https://github.com/nlohmann/json/releases/tag/v3.10.2