[feature] add hooks for using with pre-commit

[rrauenza]

PR Checklist

• A description of the changes is added to the description of this PR.
• If there is a related issue, make sure it is linked to this PR.
• If you've fixed a bug or added code that should be tested, add tests!
• Documentation in docs is updated

Description of changes

Second try at this based on previous reviews -- do we still want to try to provide a hooks file?

@wpdonders

Reference: #124

[fpgmaas]

Suggestion to replace the NOTE: with an admonition using the !!! info syntax.

Also, maybe we should state more explicitly that the pre-commit hook should be run within the virtual environment, and we could replace the word virtualenv with virtual environment.

!!! important

    This will only pull in the pre commit hooks config file from the version you have specified.  The actual version of deptry that will be run will be the first one found in your path, so you will need to add deptry to your local virtual environment for the pre-commit.
    
    For the pre-commit hook to run successfully, it should be run within the virtual environment of the project to be scanned, since it needs access to the metadata of the installed packages.
   

[fpgmaas]

Looks good to me, thanks for your contribution. I tested it out locally on another repository and it seems to work great!

I added one comment about the documentation.

[fpgmaas]

@rrauenza

[rrauenza]

@fpgmaas ,

Will github render the !!! info ...? I'm not seeing it rendered here (and "important" doesn't seem to be a valid tag?):

https://github.com/rrauenza/deptry/blob/feature/docs/docs/usage.md

[fpgmaas]

@fpgmaas ,

Will github render the !!! info ...? I'm not seeing it rendered here (and "important" doesn't seem to be a valid tag?):

https://github.com/rrauenza/deptry/blob/feature/docs/docs/usage.md

@rrauenza Good that you check. This file is used by mkdocs to generate the documentation for deptry. The syntax you see there is an admonition; https://squidfunk.github.io/mkdocs-material/reference/admonitions/

So it's no problem you don't see it being rendered properly on Github. Hope that clarifies it!