Test template sync using proxy

[lhellebr]

Tests for of SAT-27349.

UI part requires SatelliteQE/airgun#1621

Draft because it contains a workaround for discovered regressions and because the feature hasn't been merged yet.

[lhellebr]

trigger: test-robottelo
pytest: tests/foreman/api/test_templatesync.py::TestTemplateSyncTestCase::test_positive_export_all_templates_to_repo tests/foreman/cli/test_templatesync.py::TestTemplateSyncTestCase::test_positive_import_dir_filtered tests/foreman/ui/test_templatesync.py::test_positive_import_templates
airgun: 1621

[Satellite-QE]

PRT Result

Build Number: 9325
Build Status: UNSTABLE
PRT Comment: pytest tests/foreman/api/test_templatesync.py::TestTemplateSyncTestCase::test_positive_export_all_templates_to_repo tests/foreman/cli/test_templatesync.py::TestTemplateSyncTestCase::test_positive_import_dir_filtered tests/foreman/ui/test_templatesync.py::test_positive_import_templates --external-logging
Test Result : ====== 8 failed, 4 passed, 16 skipped, 180 warnings in 2224.96s (0:37:04) ======

[lhellebr]

PRT results as expected. Tests where proxy is used fail. Tests where it is not used pass. I expect everything to start passing once PR theforeman/foreman_templates#191 is merged in Foreman.

Note: SSH tests are currently being skipped due to SAT-28933.