[Fix] Include .gitattributes file to enforce LF line endings for all python files

Fixes

Fixes #204 by @egbadon-victor

Description

This PR enforces the LF line endings for all python files in the creativecommons/legaldb repository.

Technical details

This is especially important because the docker container runs a linux enviroment, which does not explicitly know how to deal with files with line endings CRLF. Git provides a way to solve this using the .gitattributes file. This file specifies the encoding of files in both the repository and working directory. This will ensure consistent results, no matter the OS of the machine used to develop or run this project.

Tests

Clone the creativecommons/legaldb using powershell or cmd (windows native terminals) to your windows machine
Follow the instructions in the read.me file to setup the dev enviroment
You will see an error saying, /usr/bin/env: ‘python3\r’: No such file or directory
Include a .gitattributes file with the content *.py text eol=lf
Clone this modified repository to your windows machine using any terminal of your choice (powershell or cmd doesn't matter)
Follow the instructions in the read.me file to setup the dev enviroment
You should see the app and dbcontainer started and running with no errors

Screenshots

Checklist

[x] My pull request has a descriptive title (not a vague title like Update index.md).
[x] My pull request targets the default branch of the repository (main or master).
[x] My commit messages follow best practices.
[x] My code follows the established code style of the repository.
[x] I added or updated tests for the changes I made (if applicable).
[x] I added or updated documentation (if applicable).
[x] I tried running the project locally and verified that there are no visible errors.

Developer Certificate of Origin

For the purposes of this DCO, "license" is equivalent to "license or public domain dedication," and "open source license" is equivalent to "open content license or public domain dedication."

Developer Certificate of Origin

``` Developer Certificate of Origin Version 1.1 Copyright (C) 2004, 2006 The Linux Foundation and its contributors. 1 Letterman Drive Suite D4700 San Francisco, CA, 94129 Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. Developer's Certificate of Origin 1.1 By making a contribution to this project, I certify that: (a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or (b) The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or (c) The contribution was provided directly to me by some other person who certified (a), (b) or (c) and I have not modified it. (d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved. ```

creativecommons / legaldb