Remove shell prompts from commands in README.md [ci skip]

Author: mpeterv

README.md

@@ -24,10 +24,10 @@ Luacheck supports checking Lua files using syntax of Lua 5.1, Lua 5.2, Lua 5.3 a
 
 ## Installation
 
-The easiest way to install Luacheck is to use [LuaRocks](https://luarocks.org/). From your command line run the following command:
+The easiest way to install Luacheck is to use [LuaRocks](https://luarocks.org/). From your command line run the following command (using `sudo` if necessary):
 
-```bash
-$ luarocks install luacheck # prepend with sudo if necessary
+```
+luarocks install luacheck
 ```
 
 If it is not possible to install [LuaFileSystem](http://keplerproject.github.io/luafilesystem/) in your environment, use `luarocks install luacheck --deps-mode=none`. For parallel checking Luacheck additionally requires [LuaLanes](https://github.com/LuaLanes/lanes), which can be installed using LuaRocks as well.
@@ -45,7 +45,10 @@ For manual installation, only a Lua interpreter binary is required.
 After Luacheck is installed, run `luacheck` program from the command line. Pass a list of files, [rockspecs](https://github.com/keplerproject/luarocks/wiki/Rockspec-format) or directories (requires LuaFileSystem) to be checked:
 
 ```
-$ luacheck src extra_file.lua another_file.lua
+luacheck src extra_file.lua another_file.lua
+```
+
+```
 Checking src/good_code.lua               OK
 Checking src/bad_code.lua                3 warnings