Use requirements.txt instead of pipenv requirements

[JingHHe]

Description

When deploy the service with github actions workflow, it reports the error:
pipenv run pip install -r <(pipenv requirements) --target layer/python ERROR: Could not open requirements file: [Errno 2] No such file or directory: '/dev/fd/63'

To avoid stdout redirect, I update the logic to use the requirements.txt directly for pip install.

Remark

For automation please see closing-issues-using-keywords

[DanielRDias]

@dependabot rebase