Merge ~chad.smith/cloud-init:fix/tox-on-disco into cloud-init:master

[Chad Smith]

tox: fix disco httpretty dependencies for py37

LP: #1813361

[Ryan Harper (raharper)]

One question, how do we distinguish missing py27 on valid releases versus Disco (or others) where it isn't?

194a4dc... by Chad Smith on 2019-01-25

drop skip_missing_interpreters as we can handle that in CI

[Ryan Harper (raharper)]

Fixed commit message and approved.

review: Approve

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:b589421f5bf6842677f74c44a8d8a7de80079493
https://jenkins.ubuntu.com/server/job/cloud-init-ci/537/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
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review: Approve (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:194a4dcbccf8b8469c53404816cd1b58c0347670
https://jenkins.ubuntu.com/server/job/cloud-init-ci/538/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/cloud-init-ci/538/rebuild

review: Approve (continuous-integration)

diff --git a/tox.ini b/tox.ini
index d983348..d371720 100644
--- a/tox.ini
+++ b/tox.ini
@@ -75,7 +75,7 @@ deps =
     jsonpatch==1.16
     six==1.10.0
     # test-requirements
-    httpretty==0.8.6
+    httpretty==0.9.6
     mock==1.3.0
     nose==1.3.7
     unittest2==1.1.0