add yaml environments for the worker and the scheduler

This MR adds conda environments for the worker and the scheduler in the new nightlies.

The files were created following procedure described in !655 (comment 4670995):

conda create -c conda-forge -p worker python=3.9
conda activate /tmp/worker/
conda install -c conda-forge celery flower lbplatformutils mysqlclient
conda env export --no-builds -p worker > worker_env.yml

and

conda create -c conda-forge -p scheduler python=3.9
conda activate /tmp/scheduler/
conda install -c conda-forge luigi GitPython celery flower lbplatformutils mysqlclient PyYaml tabulate requests cloudant
conda env export --no-builds -p scheduler > scheduler_env.yml

and manual addition of configurator and our packages to the pip section.