let's check for potential markdown issues (#104)

**What this PR does / why we need it**:

We should make sure, that we don't have any broken links in our spec!

.github/.markdown-link-check.json

@@ -0,0 +1,13 @@
+{
+    "replacementPatterns": [
+        {
+            "pattern": "^/",
+            "replacement": "/github/workspace/"
+        }
+    ],
+    "ignorePatterns": [
+        {
+            "pattern": "^http[s]*://localhost.*"
+        }
+    ]
+}

.github/.markdownlint.yml

@@ -0,0 +1,4 @@
+default: true
+
+MD013: false #https://github.com/DavidAnson/markdownlint/blob/HEAD/doc/Rules.md#md013
+MD033: false #https://github.com/DavidAnson/markdownlint/blob/HEAD/doc/Rules.md#md033

.github/workflows/markdown-analysis.yml

@@ -0,0 +1,28 @@
+name: markdown-analysis-workflow
+
+on:
+    push:
+        branches:
+        - main
+    pull_request:
+        branches:
+        - main
+        paths:
+        - '**/*.md'
+
+jobs:
+    markdown-analysis-job:
+        runs-on: ubuntu-latest
+        name: 'github actions: markdownlint'
+        steps:
+        -   name: Checkout repository
+            uses: actions/checkout@v3
+        -   name: markdownlint
+            uses: nosborn/[email protected]
+            with:
+                files: .
+                config_file: ./.github/.markdownlint.yml
+        -   name: markdown link check
+            uses: gaurav-nelson/github-action-markdown-link-check@v1
+            with:
+                config-file: ./.github/.markdown-link-check.json