fix(styleguide): minor syntax and text formatting fixes (#2579)

Author: suryart

public/docs/ts/latest/guide/style-guide.jade

@@ -1444,7 +1444,7 @@ a(href="#toc") Back to top
 
 .s-rule.do
   :marked
-    **Do** put a singleton service whose instance wil be shared throughout the application in the `CoreModule` (e.g. `ExceptionService` and `LoggerService`).
+    **Do** put a singleton service whose instance will be shared throughout the application in the `CoreModule` (e.g. `ExceptionService` and `LoggerService`).
 
 .s-rule.do
   :marked
@@ -1940,8 +1940,6 @@ a(href="#toc") Back to top
 :marked
   ## Directives
 
-a(href="#toc") Back to top
-
 .l-main-section
 :marked
   ### <a id="06-01"></a>Use directives to enhance an element