Remove db set up from python unittests

Remove setup of MySQL and PostgreSQL openstack_citest databases from
python27, python34, pypy, and periodic-python27 jobs.

Repositories needing database setup can use the -db variants like
python27. Repositories where database setup needs has been identified
have been converted already.

There was an announcement email as well:
http://lists.openstack.org/pipermail/openstack-dev/2016-March/090052.html

Change-Id: I984eeb2db72ee14d970f1c7916bdc6df29b1bf9b

jenkins/jobs/python-bitrot-jobs.yaml

@@ -10,14 +10,6 @@
       - zuul-git-branch-prep-upper-constraints:
           branch: '{branch}'
       - install-distro-packages
-      # TODO(jaegerandi): Remove database job once all repos needing
-      # database setup are moved over to the corresponding -db job.
-      - mysql-prep
-      - pgsql-prep
-      - mysql-db:
-          db_name: openstack_citest
-      - pgsql-db:
-          db_name: openstack_citest
       - revoke-sudo
       - python27
       - assert-no-extra-files

jenkins/jobs/python-jobs.yaml

@@ -11,14 +11,6 @@
           template-name: "{template-name}"
       - gerrit-git-prep
       - install-distro-packages
-      # TODO(jaegerandi): Remove database job once all repos needing
-      # database setup are moved over to the corresponding -db job.
-      - mysql-prep
-      - pgsql-prep
-      - mysql-db:
-          db_name: openstack_citest
-      - pgsql-db:
-          db_name: openstack_citest
       - revoke-sudo
       - coverage:
           env: cover
@@ -106,14 +98,6 @@
           template-name: "{template-name}"
       - zuul-git-prep-upper-constraints
       - install-distro-packages
-      # TODO(jaegerandi): Remove database job once all repos needing
-      # database setup are moved over to the corresponding -db job.
-      - mysql-prep
-      - pgsql-prep
-      - mysql-db:
-          db_name: openstack_citest
-      - pgsql-db:
-          db_name: openstack_citest
       - revoke-sudo
       - python27
       - assert-no-extra-files
@@ -201,14 +185,6 @@
           template-name: "{template-name}"
       - zuul-git-prep-upper-constraints
       - install-distro-packages
-      # TODO(jaegerandi): Remove database job once all repos needing
-      # database setup are moved over to the corresponding -db job.
-      - mysql-prep
-      - pgsql-prep
-      - mysql-db:
-          db_name: openstack_citest
-      - pgsql-db:
-          db_name: openstack_citest
       - revoke-sudo
       - python34
       - assert-no-extra-files
@@ -264,14 +240,6 @@
           template-name: "{template-name}"
       - zuul-git-prep-upper-constraints
       - install-distro-packages
-      # TODO(jaegerandi): Remove database job once all repos needing
-      # database setup are moved over to the corresponding -db job.
-      - mysql-prep
-      - pgsql-prep
-      - mysql-db:
-          db_name: openstack_citest
-      - pgsql-db:
-          db_name: openstack_citest
       - revoke-sudo
       - pypy
       - assert-no-extra-files