feat(travis): use dist: bionic

* Move `dist` in `.travis.yml` to the top to apply it for Cirrus-based
  formulas as well

ssf/defaults.yaml

@@ -14,8 +14,8 @@ ssf_node_anchors:
             #       release phase via. `pre-commit_semantic-release.sh`
             #       An alternative method could be to use:
             #       `git describe --abbrev=0 --tags`
-            title: 'chore: use `semantic-release` cross-formula standard structure'
-            body: '* Automated using https://github.com/myii/ssf-formula/pull/24'
+            title: 'ci(travis): use `dist: bionic`'
+            body: '* Automated using https://github.com/myii/ssf-formula/pull/22'
           github:
             owner: saltstack-formulas
             repo: ''
@@ -110,7 +110,7 @@ ssf_node_anchors:
           post: []
         travis:
           addons: {}
-          dist: xenial
+          dist: bionic
         use_cirrus_ci: false
         use_tofs: false
         yamllint:

ssf/files/default/.travis.yml

@@ -2,6 +2,7 @@
 # vim: ft=yaml
 ---
 {%- from tplroot ~ "/libcimatrix.jinja" import format_ci_matrix with context %}
+dist: {{ travis.dist }}
 stages:
   {%- if platforms and not use_cirrus_ci %}
   - test
@@ -14,7 +15,6 @@ stages:
 sudo: required
 cache: bundler
 language: ruby
-dist: {{ travis.dist }}
 
 services:
   - docker

ssf/formulas.yaml

@@ -1202,6 +1202,8 @@ ssf:
         travis:
           # Facing errors with `xenial` at time of adding
           # https://travis-ci.org/myii/ufw-formula/jobs/561205378#L906
+          # Persisting with `bionic` as well
+          # https://travis-ci.org/myii/ufw-formula/jobs/581764920#L807
           dist: trusty
         use_tofs: true
       semrel_files: *semrel_files_default