docs: in toh-pt5, navigate back to home page after going to `/heroes` (#42279)
docs: in toh-pt5, navigate back to home page after going to `/heroes` (#42279)

This fixes an issue in part 5 of the Tour of Heroes tutorial on
angular.io. At the end of the `Add RouterOutlet` section, the reader navigates to
`"/heroes"`. The next section, `Add a navigation link`, instructs the user to click ona link on the dashboard page to navigate to the heroes page. This is problematic because the previous section instructed the reader to navigate to the heroes page, not the dashboard. It assumes, the reader is on the dashboard page.

Fixes issue by instructing the reader to navigate back to the dashboard
after navigating to `"/heroes"` in the `Add RouterOutlet` section.

resolves #41212

PR Close #42279

mgechev/angular,brandonroberts/angular,brandonroberts/angular,ocombe/angular,gnomeontherun/angular,JiaLiPassion/angular,shairez/angular,ocombe/angular,angular-indonesia/angular,gkalpak/angular,mgechev/angular,gnomeontherun/angular,brandonroberts/angular,gkalpak/angular,ocombe/angular,JiaLiPassion/angular,gkalpak/angular,manekinekko/angular,manekinekko/angular,angular/angular,JiaLiPassion/angular,manekinekko/angular,gkalpak/angular,angular-indonesia/angular,shairez/angular,mgechev/angular,JiaLiPassion/angular,ocombe/angular,shairez/angular,mgechev/angular,manekinekko/angular,angular/angular,gnomeontherun/angular,angular-indonesia/angular,brandonroberts/angular,brandonroberts/angular,mgechev/angular,manekinekko/angular,angular-indonesia/angular,brandonroberts/angular,gnomeontherun/angular,angular/angular,shairez/angular,ocombe/angular,angular/angular,shairez/angular,manekinekko/angular,ocombe/angular