feat(docs): Add separators to README.md (#5784) r=@shane-tomlinson

Thank you very much @tiagomoraismorgado88!

README.md

@@ -17,6 +17,8 @@ Static server that hosts [Firefox Account sign up](https://accounts.firefox.com)
 * [Servers](#servers)
 * [License](#license)
 
+---
+
 ## Quick Start
 
 Clone the repository, make sure you have [required prerequisites](https://github.com/mozilla/fxa-local-dev#dependencies) installed.
@@ -27,6 +29,8 @@ If you want to install all Firefox Accounts servers locally follow the instructi
 [fxa-local-dev](https://github.com/mozilla/fxa-local-dev) to get a full development setup running.
 Please note that fxa-local-dev is the preferred way of contributing to Firefox Accounts.
 
+---
+
 ## Development Notes
 
 ### Changes to stylesheets
@@ -38,6 +42,8 @@ Now whenever a change is made to the `.scss` files, the corresponding css resour
 
 Any changes made to the scripts or the template files will automatically be reflected on page refresh.
 
+---
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 ## Testing
 
 ### Prerequisites
@@ -62,6 +68,8 @@ To change the default auth server edit `server/config/*.json` on your deployed i
 
 **Note that testing with Selenium via Docker does *not* work at present, so all testing must be carried out via your normal operating system's npm & Java tooling.**
 
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 ## Grunt Commands
 
 [Grunt](http://gruntjs.com/) is used to run common tasks to build, test, and run local servers.
@@ -78,6 +86,8 @@ To change the default auth server edit `server/config/*.json` on your deployed i
 | `grunt version` | stamp a new minor version. Updates the version number and creates a new CHANGELOG.md. |
 | `grunt version:patch` | stamp a new patch version. Updates the version number and creates a new CHANGELOG.md. |
 
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 ## Servers
 
 * latest development - https://latest.dev.lcip.org/
@@ -86,6 +96,8 @@ To change the default auth server edit `server/config/*.json` on your deployed i
 * stage - https://accounts.stage.mozaws.net/
 * production - https://accounts.firefox.com/
 
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+
 ## License
 
 MPL 2.0