remove double backticks

docs/src/quickstart.md

@@ -55,7 +55,7 @@ end
     Your model doesn't have to be called `model` - it's just a name.
 
 The following commands will create two variables, `x` and `y`, with both lower
-and upper bounds. Note the first argument is our model variable ``model``. These
+and upper bounds. Note the first argument is our model variable `model`. These
 variables are associated with this model and cannot be used in another model.
 ```jldoctest quickstart_example
 julia> @variable(model, 0 <= x <= 2)