### Why I did it
The json.hpp header file from that package is used in the sonic-swss-common build. An old version of that header file (from 2016) has been checked into the sonic-swss-common repo. However, since then, there have been changes to that header file, and starting with GCC 12 in Bookworm, generates some errors about variables being possibly uninitialized before use.
##### Work item tracking
- Microsoft ADO **(number only)**: 25027439
#### How I did it
To fix this, install the nlohmann-json3-dev package, and allow using the header file from the Debian package instead of a static checked-in version. The version in Debian Bullseye is much newer than this version.
#### How to verify it
With this change alone, sonic-swss-common will still be using the json.hpp file in its own codebase. The change to actually use the system header file instead of the local header file will happen in a separate PR in the necessary repoes.
Co-authored-by: Saikrishna Arcot <sarcot@microsoft.com>
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