Updated GET, add requirements and prep for CI/CD pipeline

What's Changed

• General update by @adamyala in #2
• fix post search. remove deprecated page list test by @adamyala in #3
• Add search action to pages by @zanderle in #4
• fix: Updates client get method by @martinalbert in #7
• Add necessary fixes to make new releases by @martinalbert in #9

New Contributors

• @adamyala made their first contribution in #2
• @zanderle made their first contribution in #4
• @martinalbert made their first contribution in #7

Full Changelog: https://github.com/ButterCMS/buttercms-python/commits/v2.0.0