Increase success rate of auto-scroll-to-target-subheading of search results

[damithc]

v1.8.4

Steps:

• Search for a topic in the text book of this site https://nus-cs2103.github.io/website-base/se-book-adapted/ e.g., search for unit testing
• Select a result that points to a sub-heading of a page
• Hit enter

Expected: Page auto-scrolls to the intended sub-heading
Actual: Most times the page scrolls to the wrong location of the page

I suspect there is a race between loading content and scrolling.

[nusjzx]

The problem is not caused by race between loading content and scrolling. I've tried scrolling after page loaded, it still can not jump to the heading.

[yamgent]

As discussed, this is not just a problem specific to search only. It happens even when you try to load through a direct link to a sub-heading:

https://markbind.github.io/markbind/userGuide/components.html#advanced-tips-and-tricks

We need to figure out how to execute code after Vue finishes loading everything (can try document.ready, or Vue.mounted event hook).