fix(jsonpath): Prevent converting date string to DateTime in JSONPath

[shiena]

Description

If you extract the date and time string with checkver/jsonpath in the manifest file, it will be converted to M/d/yyyy h:m:s tt format instead of the original string. This is due to Json.net converting to DateTime type, so it suppresses the conversion.

Motivation and Context

Closes #5129

How Has This Been Tested?

1. scoop bucket add version
2. modify goneovim-nightly.json with goneovim-nightly: Fix version Versions#618
3. modify lib/json.ps1 with this PR
4. checkver.ps1 goneovim-nightly ~/scoop/bucket/versions/bucket -f
5. update successful

Checklist:

• I have read the Contributing Guide.
• I have ensured that I am targeting the develop branch.
• I have updated the documentation accordingly.
• I have updated the tests accordingly.
• I have added an entry in the CHANGELOG.

[rashil2000]

I'm okay with this fix, but how do we ensure it doesn't break any existing manifest's checkver (because the checkver output will now be different)?

/cc @niheaven

[niheaven]

Will review it soon, should test as many as we can to ensure the change of parser type doesn't cause problems.