core.getOriginalInput() or core.getStringInput()

[eregon]

Describe the enhancement

I would like a way to get the original input string, without parsing to a number.
The main motivation is the YAML parser behaves unexpectedly for myinput: 3.0 as noted in actions/runner#849, core.getInput() will return "3" instead of the expected "3.0".
Given actions/runner#849 has seen no progress at all in years, and it could be a compatibility issue, maybe there is an easier way to address the issue.

So if we could have core.getOriginalInput("myinput") or core.getStringInput("myinput"), that would return "3.0" for myinput: 3.0. That probably means the YAML parser would need to preserve that string before interpreting it (not sure whether it does currently) and somehow pass it through to env vars and so toolkit core could access it.

This sounds to me like a fairly simple solution to actions/runner#849 without any major drawback.