Install same poetry version in local development environment as in CI
Currently, the `DEVELOPER_GUIDE` instruct to install the latest Poetry version (currently 1.5.1) to set up the local development environment, differently from the CI, which uses 1.4.2.
Install same poetry version in local development environment as in CI: Currently, the `DEVELOPER_GUIDE` instruct to install the latest Poetry version (currently 1.5.1) to set up the local development environment, differently from the CI, which uses 1.4.2.