Default to ruff-version from pyproject.toml (#30)

Closes: #9 

Changes the default behavior to:

- Search for a pyproject.toml in the repo root
- Search in project.dependencies and dependency-groups.dev for ruff
- If none is found use latest

Support for requirements.txt files can be added later

src/utils/inputs.ts

@@ -5,3 +5,4 @@ export const checkSum = core.getInput("checksum");
 export const githubToken = core.getInput("github-token");
 export const args = core.getInput("args");
 export const src = core.getInput("src");
+export const versionFile = core.getInput("version-file");