dev: set markdown as repository language with .gitattributes

Add `.gitattributes` file to configure GitHub Linguist to only consider
`.md` Markdown files

Linguist should ignore other file types

Author: practicalli-johnny

.gitattributes

@@ -0,0 +1,8 @@
+# Configure Languages for GitHub repository using Linguist
+
+# ignore all files, except for markdown
+docs/** linguist-detectable
+*.md linguist-detectable=true 
+*.css linguist-detectable=false
+*.js linguist-detectable=false
+*.html linguist-detectable=false  

.gitignore

@@ -21,5 +21,6 @@
 # ------------------------
 # Version Control
 !.gitignore
+!.gitattributes
 !.github/
 

CHANGELOG.md

@@ -1,6 +1,9 @@
 # Changelog
 
 # Unreleased
+## Added
+- dev: set markdown as repository language with `.gitattributes`
+
 ## Changed
 - clojure-cli: enhance built-in commands description
 - code-challenge: rewrite code challenges overview