Skip deploy stage unless building a tag

Author: nicoddemus

.travis.yml

@@ -14,6 +14,11 @@ script:
 after_success:
   - coveralls
 
+stages:
+- test
+- name: deploy
+  if: repo = pytest-dev/pytest-mock AND tag IS present
+
 jobs:
   include:
     - python: '3.7'

appveyor.yml

@@ -5,3 +5,5 @@ build: false  # Not a C# project
 
 test_script:
   - C:\Python36\scripts\tox
+
+skip_tags: true