[Unix] Create a framework for certbot integration tests: PART 2 (#6821)

* Second part: integration tests for certbot core

* Specific coverages

* Add comments

* Improve names

* Suspend fail-under until complete coverage

* Implement a minimal functional example

* Update certbot-ci/certbot_integration_tests/certbot_tests/conftest.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/certbot_tests/context.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/certbot_tests/context.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Fist set of corrections after review

* Fix test and test deploy hook flag

* Improve an assertion, remove conftest

* Add a test to cover all assertions. Remove the CSR logic for now

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Some corrections

* Add the http-01 test to complete coverage

* Add a comment.

* Make single requirements

* Update certbot-ci/certbot_integration_tests/certbot_tests/context.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Revert "Some corrections"

This reverts commit 6f20a060e5.

# Conflicts:
#	certbot-ci/certbot_integration_tests/certbot_tests/context.py
#	certbot-ci/certbot_integration_tests/certbot_tests/test_main.py

* Clean join

* Update certbot-ci/certbot_integration_tests/certbot_tests/context.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/certbot_tests/context.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Change assertion name

* Rewrite http auth hook as real python scripts

* Correct output in some OS

* Try a direct execution

* Fix shebang

* Correct a script

* Update certbot config

* Call explicitly with python, to be cross platform compatible

* Avoid infinite loops. Improve documentation.

* Fix syntax

tools/dev_constraints.txt

@@ -57,6 +57,7 @@ pytest-cov==2.5.1
 pytest-forked==0.2
 pytest-xdist==1.22.5
 pytest-sugar==0.9.2
+pytest-rerunfailures==4.2
 python-dateutil==2.6.1
 python-digitalocean==1.11
 PyYAML==3.13