Update plugins.md

Author: bonham000

content/concepts/plugins.md

@@ -30,7 +30,7 @@ ConsoleLogOnBuildWebpackPlugin.prototype.apply = function(compiler) {
 };
 ```
 
-T> As clever JavaScript developer you may remember the `Function.prototype.apply` method. Because of this method you can pass any function as plugin (`this` will point to the `compiler`). You can use this style to inline custom plugins in your configuration.
+T> As a clever JavaScript developer you may remember the `Function.prototype.apply` method. Because of this method you can pass any function as plugin (`this` will point to the `compiler`). You can use this style to inline custom plugins in your configuration.
 
 ## Usage