[api] Add `parseConfigFileTextToJson()` helper

[mrazauskas]

Acknowledgement

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Comment

Please consider adding the parseConfigFileTextToJson() helper. For some reason, it was not part of microsoft/typescript-go#4888.

Currently, in a workflow that uses parseJsonConfigFileContent() and a user-supplied JSON string is processed, there is no way to get and report parse diagnostics.

JSON.parse() does the job, but the quality of diagnostics is not the same. Creating a virtual file and using readConfigFile() is another workaround, but I would need to use the virtual file system only to handle this case.