doc: add blanks around code fences

BUILDING.md

@@ -665,16 +665,19 @@ during configuration if the ICU version is too old.
 #### Unix/macOS
 
 From an already-unpacked ICU:
+
 ```console
 $ ./configure --with-intl=[small-icu,full-icu] --with-icu-source=/path/to/icu
 ```
 
 From a local ICU tarball:
+
 ```console
 $ ./configure --with-intl=[small-icu,full-icu] --with-icu-source=/path/to/icu.tgz
 ```
 
 From a tarball URL:
+
 ```console
 $ ./configure --with-intl=full-icu --with-icu-source=http://url/to/icu.tgz
 ```

CPP_STYLE_GUIDE.md

@@ -186,6 +186,7 @@ class FancyContainer {
  ...
 }
 ```
+
 ## Memory Management
 
 ### Memory allocation

doc/api/child_process.md

@@ -168,6 +168,7 @@ generated output. The `command` string passed to the exec function is processed
 directly by the shell and special characters (vary based on
 [shell](https://en.wikipedia.org/wiki/List_of_command-line_interpreters))
 need to be dealt with accordingly:
+
 ```js
 exec('"/path/to/test file/test.sh" arg1 arg2');
 // Double quotes are used so that the space in the path is not interpreted as

doc/api/cli.md

@@ -70,6 +70,7 @@ added: v10.12.0
 -->
 
 Print source-able bash completion script for Node.js.
+
 ```console
 $ node --completion-bash > node_bash_completion
 $ source node_bash_completion

doc/api/console.md

@@ -498,6 +498,7 @@ This method does not display anything unless used in the inspector. The
 `console.profile()` method starts a JavaScript CPU profile with an optional
 label until [`console.profileEnd()`][] is called. The profile is then added to
 the **Profile** panel of the inspector.
+
 ```js
 console.profile('MyLabel');
 // Some code

doc/api/crypto.md

@@ -712,6 +712,7 @@ const dh = crypto.createDiffieHellmanGroup(name);
 ```
 
 `name` is taken from [RFC 2412][] (modp1 and 2) and [RFC 3526][]:
+
 ```console
 $ perl -ne 'print "$1\n" if /"(modp\d+)"/' src/node_crypto_groups.h
 modp1  #  768 bits

doc/api/dgram.md

@@ -528,6 +528,7 @@ socket.bind(1234, () => {
 
 #### Example: IPv4 Outgoing Multicast Interface
 All systems use an IP of the host on the desired physical interface:
+
 ```js
 const socket = dgram.createSocket('udp4');
 

doc/api/errors.md

@@ -70,6 +70,7 @@ Errors that occur within _Asynchronous APIs_ may be reported in multiple ways:
     // Otherwise handle the data
   });
   ```
+
 - When an asynchronous method is called on an object that is an
   [`EventEmitter`][], errors can be routed to that object's `'error'` event.
 

doc/api/esm.md

@@ -188,6 +188,7 @@ module via `import`.
   "main": "./src/index.js"
 }
 ```
+
 ```js
 // ./my-app.mjs
 

doc/api/fs.md

@@ -231,6 +231,7 @@ fs.readFileSync(new URL('file:///p/a/t/h/%2f'));
 /* TypeError [ERR_INVALID_FILE_URL_PATH]: File URL path must not include encoded
 / characters */
 ```
+
 On Windows, `file:` URLs having encoded backslash will result in a throw:
 
 ```js
@@ -3816,6 +3817,7 @@ recommended.
 
 When `file` is a file descriptor, the behavior is almost identical to directly
 calling `fs.write()` like:
+
 ```javascript
 fs.write(fd, Buffer.from(data, options.encoding), callback);
 ```

doc/api/http2.md

@@ -2459,6 +2459,7 @@ The `CONNECT` method is used to allow an HTTP/2 server to be used as a proxy
 for TCP/IP connections.
 
 A simple TCP Server:
+
 ```js
 const net = require('net');
 

doc/api/https.md

@@ -256,6 +256,7 @@ req.on('error', (e) => {
 });
 req.end();
 ```
+
 Example using options from [`tls.connect()`][]:
 
 ```js