Bump mdl from 0.13.0 to 0.15.0 (#185)

Bumps [mdl](https://github.com/mivok/markdownlint) from 0.13.0 to 0.15.0.
- [Changelog](https://github.com/markdownlint/markdownlint/blob/main/CHANGELOG.md)
- [Commits](markdownlint/markdownlint@v0.13.0...v0.15.0)

---
updated-dependencies:
- dependency-name: mdl
  dependency-version: 0.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -25,15 +25,15 @@ GEM
     base64 (0.2.0)
     benchmark (0.5.0)
     bigdecimal (3.3.1)
-    chef-utils (18.3.0)
+    chef-utils (18.8.54)
       concurrent-ruby
     coffee-script (2.4.1)
       coffee-script-source
       execjs
     coffee-script-source (1.12.2)
     colorator (1.1.0)
     commonmarker (0.23.10)
-    concurrent-ruby (1.3.4)
+    concurrent-ruby (1.3.6)
     connection_pool (2.4.1)
     console (1.34.2)
       fiber-annotation
@@ -254,11 +254,11 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.6.0)
-    mdl (0.13.0)
+    mdl (0.15.0)
       kramdown (~> 2.3)
       kramdown-parser-gfm (~> 1.1)
-      mixlib-cli (~> 2.1, >= 2.1.1)
-      mixlib-config (>= 2.2.1, < 4)
+      mixlib-cli
+      mixlib-config
       mixlib-shellout
     mercenary (0.3.6)
     metrics (0.15.0)
@@ -270,7 +270,7 @@ GEM
     mixlib-cli (2.1.8)
     mixlib-config (3.0.27)
       tomlrb
-    mixlib-shellout (3.2.7)
+    mixlib-shellout (3.3.9)
       chef-utils
     net-http (0.4.1)
       uri
@@ -295,7 +295,7 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rexml (3.4.2)
+    rexml (3.4.4)
     rouge (3.30.0)
     ruby-rc4 (0.1.5)
     rubyzip (2.3.2)
@@ -312,7 +312,7 @@ GEM
     simpleidn (0.2.3)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
-    tomlrb (2.0.3)
+    tomlrb (2.0.4)
     traces (0.18.2)
     ttfunk (1.8.0)
       bigdecimal (~> 3.1)