Add explicit conversion from json to std::string_view in conversion unit test

[taylorhoward92]

Addresses #1634 by adding explicit conversion to std::string_view.

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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 file single_include/nlohmann/json.hpp. The whole process is described here.

[coveralls]

Coverage remained the same at 100.0% when pulling 2f389cd on taylorhoward92:develop into 4fc98e0 on nlohmann:develop.

[nlohmann]

Looks good to me.

[nlohmann]

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🔖 Release item

This issue/PR will be part of the next release of the library. This template helps preparing the release notes.

Type

• ✨ New Feature
• 🐛 Bug Fix
• ⚡️ Improvement
• 🔨 Further Change
• 🔥 Deprecated function

Description

• Fix a conversion to std::string_view in the unit tests.

Contributor entry

• Taylor Howard fixed a unit test.

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[nlohmann]

Thanks!