test-local: install pycurl from source

[manics]

The test-local CI test is currently failing with

 binderhub/tests/test_build.py:87: AssertionError
----------------------------- Captured stdout call -----------------------------
failed: Error resolving ref for gh:binderhub-ci-repos/cached-minimal-dockerfile/596b52f10efb0c9befc0c4ae850cc5175297d71c: HTTP 599: error setting certificate verify locations:
  CAfile: /etc/pki/tls/certs/ca-bundle.crt
  CApath: none

@pastram-i worked out it's due to the recent 7.45.3 release of pycurl https://discourse.jupyter.org/t/suddenly-getting-oath-cert-error/24217/4

7.45.2 only has source packages, 7.45.3 introduced binary wheels which seem to be the problem.

[consideRatio]

Nice!! I added a direct link to pycurl tracked issue so we can rely on the wheels in the end