[DOC] Nested ordered lists need more indents

doc/contributing/building_ruby.md

@@ -42,29 +42,31 @@
 
 1. Download ruby source code:
 
+    Select one of the bellow.
+
     1. Build from the tarball:
 
-    Download the latest tarball from [ruby-lang.org](https://www.ruby-lang.org/en/downloads/) and
-    extract it. Example for Ruby 3.0.2:
+        Download the latest tarball from [ruby-lang.org](https://www.ruby-lang.org/en/downloads/) and
+        extract it. Example for Ruby 3.0.2:
 
-    ``` shell
-    tar -xzf ruby-3.0.2.tar.gz
-    cd ruby-3.0.2
-    ```
+        ``` shell
+        tar -xzf ruby-3.0.2.tar.gz
+        cd ruby-3.0.2
+        ```
 
     2. Build from the git repository:
 
-    Checkout the CRuby source code:
+        Checkout the CRuby source code:
 
-    ``` shell
-    git clone https://github.com/ruby/ruby.git
-    ```
+        ``` shell
+        git clone https://github.com/ruby/ruby.git
+        ```
 
-    Generate the configure file:
+        Generate the configure file:
 
-    ``` shell
-    ./autogen.sh
-    ```
+        ``` shell
+        ./autogen.sh
+        ```
 
 2. Create a `build` directory separate from the source directory: