Remove dependency as valid chunksSortMode (#1406)

As this was removed a while back, and now just gives `"dependency" is not a valid chunk sort mode`

README.md

@@ -146,7 +146,7 @@ Allowed values are as follows
 |**`cache`**|`{Boolean}`|`true`|Emit the file only if it was changed|
 |**`showErrors`**|`{Boolean}`|`true`|Errors details will be written into the HTML page|
 |**`chunks`**|`{?}`|`?`|Allows you to add only some chunks (e.g only the unit-test chunk)|
-|**[`chunksSortMode`](#plugins)**|`{String\|Function}`|`auto`|Allows to control how chunks should be sorted before they are included to the HTML. Allowed values are `'none' \| 'auto' \| 'dependency' \| 'manual' \| {Function}`|
+|**[`chunksSortMode`](#plugins)**|`{String\|Function}`|`auto`|Allows to control how chunks should be sorted before they are included to the HTML. Allowed values are `'none' \| 'auto' \| 'manual' \| {Function}`|
 |**`excludeChunks`**|`{Array.<string>}`|``|Allows you to skip some chunks (e.g don't add the unit-test chunk)|
 |**`xhtml`**|`{Boolean}`|`false`|If `true` render the `link` tags as self-closing (XHTML compliant)|