proposal: Allow SemVer compatible updates

[Blisto91]

Is your feature request related to a problem? Please describe.

Unless i'm missing something the current version only allows getting a specific release version or the latest.
I would like to be able to get the latest SemVer compatible version.
So if i were using the 0.3 version of mdbook it would automatically get 0.3.1, 0.3.2, 0.3.3 etc. as they were released.

Describe the solution you'd like

Allow a syntax like '^0.3' to get the latest minor version.
A separate SemVer option that could be set to true could also be fine

Describe alternatives you've considered

Updating the version manually so when 0.4.2 gets released i would have to update my CI.
I could also try fetching the latest minor version outside of this action and then supply that

Additional context
Examples from the actions-rs/cargo action

      - name: install mdbook
        uses: actions-rs/cargo@v1
        with:
          command: install
          args: --vers "^0.3" mdbook

[peaceiris]

Thank you for the suggestion. I will consider this.