[jsoncons] Update to version 1.0.0

[danielaparker]

If this PR updates an existing port, please uncomment and fill out this checklist:

• [x ] Changes comply with the maintainer guide.
• [x ] SHA512s are updated for each updated download.
• [x ] The "supports" clause reflects platforms that may be fixed by this new version.
• [x ] Any fixed CI baseline entries are removed from that file.
• [ x] Any patches that are no longer applied are deleted from the port's directory.
• [ x] The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• [ x] Only one version is added to each modified port's versions file.

[BillyONeal]

Thanks for the update!