Adapt to use PyPi for builds instead of RPMs

[dulek]

Main problem with RPMs is that we need to use OSP ones and these are super outdated. ART recently figured out how to enable builds based on PyPi packages going through ARTs Cachito instance. This will let us skip all the RPM hell that we have today and this commit aims to do that. In particular:

1. kuryr-requirements.txt file is added that will gather exact versions of packages that we want from PyPi.
2. Dockerfiles are adapted to install Kuryr as a Python package and not an RPM.
3. Stuff required to build Kuryr RPM is removed as it's no needed anymore.

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dulek

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[dulek]

/hold

This is strongly WiP!

[dulek]

/retest

That's just a failure to acquire the lease.

[openshift-ci[bot]]

@dulek: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/images	d0b35b63100b04b714d3405b0ea5d1f976cef3ee	link	true	/test images
ci/prow/e2e-openstack-kuryr	d0b35b63100b04b714d3405b0ea5d1f976cef3ee	link	true	/test e2e-openstack-kuryr

Full PR test history. Your PR dashboard.

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[openshift-bot]

Issues go stale after 90d of inactivity.

Mark the issue as fresh by commenting /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close. Exclude this issue from closing by commenting /lifecycle frozen.

If this issue is safe to close now please do so with /close.

/lifecycle stale

[openshift-bot]

Stale issues rot after 30d of inactivity.

Mark the issue as fresh by commenting /remove-lifecycle rotten. Rotten issues close after an additional 30d of inactivity. Exclude this issue from closing by commenting /lifecycle frozen.

If this issue is safe to close now please do so with /close.

/lifecycle rotten /remove-lifecycle stale

[dulek]

We might want to revisit this at some point, but right now it's not a priority.