Merge "Drop support for python 3.5"

.zuul.yaml

@@ -232,11 +232,11 @@
         - tox-linters:
             vars:
               tox_install_bindep: false
-        - tox-py35:
+        - tox-py36:
             irrelevant-files:
               - zuul/cmd/migrate.py
               - playbooks/zuul-migrate/.*
-            nodeset: ubuntu-xenial
+            nodeset: ubuntu-bionic
             timeout: 4800  # 80 minutes
             vars: &zuul_tox_vars
                 test_setup_environment:
@@ -282,11 +282,11 @@
         - tox-linters:
             vars:
               tox_install_bindep: false
-        - tox-py35:
+        - tox-py36:
             irrelevant-files:
               - zuul/cmd/migrate.py
               - playbooks/zuul-migrate/.*
-            nodeset: ubuntu-xenial
+            nodeset: ubuntu-bionic
             timeout: 4800  # 80 minutes
             vars: *zuul_tox_vars
         - tox-py38:

releasenotes/notes/python35-fd8e7f7f577b55e5.yaml

@@ -0,0 +1,4 @@
+---
+upgrade:
+  - |
+    Support for running Zuul under Python 3.5 has been dropped.

setup.cfg

@@ -6,7 +6,7 @@ description-file =
 author = Zuul Team
 author-email = zuul-discuss@lists.zuul-ci.org
 home-page = https://zuul-ci.org/
-python-requires = >=3.5
+python-requires = >=3.6
 classifier =
     Intended Audience :: Information Technology
     Intended Audience :: System Administrators
@@ -14,7 +14,6 @@ classifier =
     Operating System :: POSIX :: Linux
     Programming Language :: Python
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8