Bump version to 3.0.0-dev0, remove deprecated functionality and implement announced breaking changes (#873)

* Bump verison to 3.0.0-dev0.

* Change check mode behavior for *_pipe modules.

* Remove PyOpenSSL backend.

* Remove PyOpenSSL setup.

* Change default of asn1_base64.

* Remove deprecated common module utils.

* Remove get_default_argspec().

* Mark two methods as abstract.

* Remove ACME v1 support.

* Remove retrieve_acme_v1_certificate().

* Remove deprecated docs fragment.

* Change meaning of mode parameter.

* Mark no longer used option as 'to deprecate'.

tests/unit/plugins/module_utils/acme/test_challenges.py

@@ -68,20 +68,6 @@ def test_challenge_from_to_json():
     assert challenge.token == "foo"
     assert challenge.to_json() == data
 
-    data = {
-        "uri": "xxx",
-        "type": "type",
-        "status": "valid",
-    }
-    client.version = 1
-    challenge = Challenge.from_json(client, data)
-    assert challenge.data == data
-    assert challenge.type == "type"
-    assert challenge.url == "xxx"
-    assert challenge.status == "valid"
-    assert challenge.token is None
-    assert challenge.to_json() == data
-
 
 def test_authorization_from_to_json():
     client = MagicMock()
@@ -154,30 +140,6 @@ def test_authorization_from_to_json():
         "wildcard": True,
     }
 
-    client.version = 1
-
-    data = {
-        "challenges": [],
-        "identifier": {
-            "type": "dns",
-            "value": "example.com",
-        },
-    }
-    authz = Authorization.from_json(client, data, "xxx")
-    assert authz.url == "xxx"
-    assert authz.status == "pending"
-    assert authz.identifier == "example.com"
-    assert authz.identifier_type == "dns"
-    assert authz.challenges == []
-    assert authz.to_json() == {
-        "uri": "xxx",
-        "challenges": [],
-        "identifier": {
-            "type": "dns",
-            "value": "example.com",
-        },
-    }
-
 
 def test_authorization_create_error():
     client = MagicMock()