feat(flask): adding flask decorators as a package extra

[omercnet]

Related Issues

Fixes https://github.com/descope/etc/issues/2539

Description

Making flask an extra package of descope python-sdk
Extra means it is not installed by default, and only when adding the extra flag it will also install Flask dependencies that are needed.

• Adjusted the sample scripts to work with the package itself
• Added typing annotations
• Reduced test coverage of the new code
• Also added vscode settings and recommended extensions for ease development
• Removed tox from pre-commit as it's a huge overhead for every commit, devs should test locally before committing, and tests still run in CI still.

[github-actions]

Coverage report

The coverage rate went from 98.12% to 98.12% ⬇️

None of the new lines are part of the tested code. Therefore, there is no coverage data about them.