mardownlint: relax rules

Start with [relaxed rules](https://github.com/DavidAnson/markdownlint/blob/2b2dc27f24a16a2afdf66d850a247f7ce02df6c8/style/relaxed.json]
and do not require blank lines, as they seem to be only be required for
the `kramdown` parser which we do not use.

Author: silvestre

.markdownlint.json

@@ -1,6 +1,13 @@
 {
-  "comment": "Relaxed rules",
-  "default": true,
-  "line-length": false
+    "comment": "Relaxed rules + disable blank lines",
+    "default": true,
+    "whitespace": false,
+    "line_length": false,
+    "ul-start-left": false,
+    "ul-indent": false,
+    "no-inline-html": false,
+    "no-bare-urls": false,
+    "fenced-code-language": false,
+    "first-line-h1": false,
+    "blank_lines": false
 }
-

.tool-versions

@@ -13,3 +13,4 @@ bosh 7.0.1
 gcloud 403.0.0
 cf 8.5.0
 actionlint 1.6.22
+direnv 2.32.1