Markdown linter (#5494)

* linter

* Add markdown linter

* add env

* only check markdown

* Add token

* Update .github/workflows/test-suite.yml

* Markdown linter

* Exit code

* Update script

* rename

* mdlint

* Add an empty line after end of file

* Testing disable

* add text

* update mdlint.sh

* ori validator inclusion

* Add config yml file

* Remove MD041 and fix advanced-datadir file

* FIx validator inclusion file conflict

* Merge branch 'unstable' into markdown-linter

* change files

* Merge branch 'markdown-linter' of https://github.com/chong-he/lighthouse into markdown-linter

* mdlint

* Remove MD025

* Remove MD036

* Remove MD045

* Removr MD001

* Set MD028 to false

* Remove MD024

* Remove MD055

* Remove MD029

* Remove MD040

* Set MD040 to false

* Set MD033 to false

* Set MD013 to false

* Rearrange yml file

* Update mdlint.sh and test

* Test remove fix

* Test with fix

* Test with space

* Fix summary indentation

* Test mdlint.sh

* Update mdlint.sh

* Test

* Update

* Test fix

* Test again

* Fix

* merge into check-code

* Update scripts/mdlint.sh

Co-authored-by: Mac L <mjladson@pm.me>

* Update scripts/mdlint.sh

Co-authored-by: Mac L <mjladson@pm.me>

* Remove set -e

* Add comment

* Merge pull request #7 from chong-he/unstable

Merge unstable to markdown branch

* mdlint

* Merge branch 'unstable' into markdown-linter

* mdlint

book/src/pi.md

@@ -4,22 +4,21 @@
 
 Tested on:
 
- - Raspberry Pi 4 Model B (4GB)
- - `Ubuntu 20.04 LTS (GNU/Linux 5.4.0-1011-raspi aarch64)`
-
+- Raspberry Pi 4 Model B (4GB)
+- `Ubuntu 20.04 LTS (GNU/Linux 5.4.0-1011-raspi aarch64)`
 
 *Note: [Lighthouse supports cross-compiling](./cross-compiling.md) to target a
 Raspberry Pi (`aarch64`). Compiling on a faster machine (i.e., `x86_64`
 desktop) may be convenient.*
 
-### 1. Install Ubuntu
+## 1. Install Ubuntu
 
 Follow the [Ubuntu Raspberry Pi installation instructions](https://ubuntu.com/download/raspberry-pi). **A 64-bit version is required**
 
 A graphical environment is not required in order to use Lighthouse.  Only the
 terminal and an Internet connection are necessary.
 
-### 2. Install Packages
+## 2. Install Packages
 
 Install the Ubuntu dependencies:
 
@@ -32,7 +31,7 @@ sudo apt update && sudo apt install -y git gcc g++ make cmake pkg-config llvm-de
 > - If there are difficulties, try updating the package manager with `sudo apt
 >   update`.
 
-### 3. Install Rust
+## 3. Install Rust
 
 Install Rust as per [rustup](https://rustup.rs/):
 
@@ -47,7 +46,7 @@ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
 >   be found, run `source $HOME/.cargo/env`. After that, running `cargo version` should return the version, for example `cargo 1.68.2`.
 > - It's generally advisable to append `source $HOME/.cargo/env` to `~/.bashrc`.
 
-### 4. Install Lighthouse
+## 4. Install Lighthouse
 
 ```bash
 git clone https://github.com/sigp/lighthouse.git