chore(pipeline): add action to lint markdown files (#1593)

* add markdownlint action

* add markdownlint config

* add dummy change to MD file

* rename job

* run on master branch

* remove ignore files

* add dummy change

* revert dummy change

* Update markdown.yml

* Update .markdownlint.yml

* Update README.md

* Update .markdownlint.yml

* Update markdown.yml

.github/workflows/markdown.yml

@@ -0,0 +1,22 @@
+name: "Documentation"
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+    paths:
+      - '**/*.md'
+
+jobs:
+  markdownlint:
+    runs-on: ubuntu-latest
+    name: 'Format'
+    steps:
+    - uses: actions/checkout@v2
+    - name: Markdown Linting
+      uses: nosborn/github-action-markdown-cli@v1.1.1
+      with:
+        files: .

.markdownlint.yml

@@ -0,0 +1,24 @@
+default: true
+
+# ignore
+MD013: false #line-length
+MD033: false #no-inline-html
+
+# TODO: fix in separate PR
+MD001: false #heading-increment/header-increment
+MD004: false #ul-style
+MD012: false #no-multiple-blanks
+MD007: false #ul-indent
+MD022: false #blanks-around-headings/blanks-around-headers
+MD024: false #no-duplicate-heading/no-duplicate-header
+MD026: false #no-trailing-punctuation
+MD030: false #list-marker-space
+MD031: false #blanks-around-fences
+MD032: false #blanks-around-lists
+MD036: false #no-emphasis-as-heading/no-emphasis-as-header
+MD038: false #no-space-in-code
+MD039: false #no-space-in-links
+MD040: false #fenced-code-language
+MD042: false #no-empty-links
+MD041: false #first-line-heading/first-line-h1
+MD046: false #code-block-style