refactor(docs): dev-guide: styleguide: add markdown table example

docs/developers-guide/styleguide.md

@@ -80,3 +80,20 @@ most important bullet points:
         > Some sentence that is very long,
         > therefore it has punctuation
         > and has absolutely no sense at all.
+
+- tables have to be formatted in code
+
+    ??? example
+        __bad:__
+        ```markdown
+        ||column 1|
+        |:-|:-|
+        |__row 1__|cell 1|
+        ```
+
+        __good:__
+        ```markdown
+        |           | column 1 |
+        | :-------- | :------- |
+        | __row 1__ | cell 1   |
+        ```