style(yamllint): apply rule quoted-strings throughout the formula

* Specifically: `quote-type: 'single'`

.travis.yml

@@ -2,23 +2,23 @@
 # vim: ft=yaml
 ---
 ## Machine config
-dist: bionic
+dist: 'bionic'
 
 ## Stages and jobs matrix
 stages:
   - test
-  - name: release
-    if: branch = master AND type != pull_request
+  - name: 'release'
+    if: 'branch = master AND type != pull_request'
 jobs:
   include:
     ## Define the test stage that runs the linters (and testing matrix, if applicable)
 
     # Run all of the linters in a single job
-    - language: node_js
-      node_js: lts/*
-      env: Lint
+    - language: 'node_js'
+      node_js: 'lts/*'
+      env: 'Lint'
       name: 'Lint: salt-lint, yamllint, rubocop & commitlint'
-      before_install: skip
+      before_install: 'skip'
       script:
         # Install and run `salt-lint`
         - pip install --user salt-lint
@@ -37,12 +37,12 @@ jobs:
         - commitlint-travis
 
     ## Define the release stage that runs `semantic-release`
-    - stage: release
-      language: node_js
-      node_js: lts/*
-      env: Release
+    - stage: 'release'
+      language: 'node_js'
+      node_js: 'lts/*'
+      env: 'Release'
       name: 'Run semantic-release inc. file updates to AUTHORS, CHANGELOG & FORMULA'
-      before_install: skip
+      before_install: 'skip'
       script:
         # Update `AUTHORS.md`
         - export MAINTAINER_TOKEN=${GH_TOKEN}
@@ -54,7 +54,7 @@ jobs:
         - npm install @semantic-release/exec@3 -D
         - npm install @semantic-release/git@7 -D
       deploy:
-        provider: script
+        provider: 'script'
         skip_cleanup: true
         script:
           # Run `semantic-release`

.yamllint

@@ -2,7 +2,7 @@
 # vim: ft=yaml
 ---
 # Extend the `default` configuration provided by `yamllint`
-extends: default
+extends: 'default'
 
 # Files to ignore completely
 # 1. All YAML files under directory `node_modules/`, introduced during the Travis run
@@ -48,3 +48,5 @@ rules:
   octal-values:
     forbid-implicit-octal: true
     forbid-explicit-octal: true
+  quoted-strings:
+    quote-type: 'single'

pillar.example

@@ -3,9 +3,9 @@
 ---
 ssf:
   ### Your local configuration
-  formulas_path: /local/path/to/formulas/directory
-  user: your_user
-  group: your_group
+  formulas_path: '/local/path/to/formulas/directory'
+  user: 'your_user'
+  group: 'your_group'
 
   git:
     ### Override the tracking branch for the upstream repo
@@ -17,7 +17,7 @@ ssf:
       options: '--no-gpg-sign'
     ### Your GitHub configuration
     github:
-      user: your_github_username
+      user: 'your_github_username'
       ### Local file to capture the GitHub API response when automatically
       ### creating the PR, prevents spamming the Salt output;
       ### Default shown below will be used if left commented out
@@ -41,7 +41,7 @@ ssf:
         ### This is a necessary override since the default script does not
         ### contain a GitHub API token; copy the file to `your_directory`
         ### and simply add your personal token at the top of the script
-        source: salt://ssf/files/your_directory/git/git_30_create_PR.sh
+        source: 'salt://ssf/files/your_directory/git/git_30_create_PR.sh'
 
   ### Any customisations to the formulas can be made here
   ### Usually, this is unnecessary but a likely override could be an upstream tracking
@@ -52,18 +52,18 @@ ssf:
         git:
           # Override the names of the local tracking branches to use
           branch:
-            upstream: my_upstream_tracking_branch
+            upstream: 'my_upstream_tracking_branch'
           github:
             # Override the configuration of the remotes
             remote:
               # The upstream formula repo
               upstream:
-                name: upstream
-                branch: master
+                name: 'upstream'
+                branch: 'master'
               # Your fork of the repo
               fork:
-                name: origin
-                branch: master
+                name: 'origin'
+                branch: 'master'
 
   ### No formulas or files are active by default
   ### State the formulas and files to work through when running the formula