exclude extraneous files from package

[baywet]

similar to https://github.com/microsoftgraph/msgraph-sdk-python-core/pull/709 those extra files slow down the installation, and can pose security issues like this https://github.com/microsoftgraph/msgraph-sdk-php-core/security/advisories/GHSA-mhhp-c3cm-2r86 directories to be excluded:

• .github
• docs files to be excluded:
• .gitignore
• .release-please-manifest
• CHANGELOG.md
• CODE_OF_CONDUCT.md
• CONTRIBUTING.md
• release-please-config
• UPGRADING.md

to test simply run python -m build locally, and check what's in the archive under dist