add a ci step for Json_Diagnostic_Positions

[hnampally]

This PR brings the change to add a CI step for the new feature Json_Diagnostic_Positions

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Pull request checklist

Read the Contribution Guidelines for detailed information.

• Changes are described in the pull request, or an existing issue is referenced.
• The test suite compiles and runs without error.
• Code coverage is 100%. Test cases can be added by editing the test suite.
• The source code is amalgamated; that is, after making changes to the sources in the include/nlohmann directory, run make amalgamate to create the single-header files single_include/nlohmann/json.hpp and single_include/nlohmann/json_fwd.hpp. The whole process is described here.

[coveralls]

coverage: 99.639%. remained the same
when pulling c1e8021 on hnampally:develop
into 4f64d8d on nlohmann:develop.

[nlohmann]

Please sign-off your commit(s).

[hnampally]

Please sign-off your commit(s).

I made the changes and and pushed this commit 2d04d40 from the browser, so I think it was not properly signed off, sorry about that.

[nlohmann]

Please sign-off your commit(s).

I made the changes and and pushed this commit 2d04d40 from the browser, so I think it was not properly signed off, sorry about that.

Do you have access to https://github.com/nlohmann/json/pull/4579/checks?check_run_id=35047024834? This contains an explanation how to fix this.

[hnampally]

Please sign-off your commit(s).

I made the changes and and pushed this commit 2d04d40 from the browser, so I think it was not properly signed off, sorry about that.

Do you have access to https://github.com/nlohmann/json/pull/4579/checks?check_run_id=35047024834? This contains an explanation how to fix this.

Yes, thanks for the pointer, I will fix and push it shortly.

[nlohmann]

Looks good to me.

[nlohmann]

Thanks!