Add heap part js code

[what-is-me]

If this PR is related to coding or code translation, please read the contribution guideline, fill out the checklist, and paste the console outputs to the PR.

• I've tested the code and ensured the outputs are the same as the outputs of reference codes.
• I've checked the codes (formatting, comments, indentation, file header, etc) carefully.
• The code does not rely on a particular environment or IDE and can be executed on a standard system (Win, macOS, Ubuntu).

输入列表并建堆后
堆的数组表示：    
[
  9, 8, 6, 6, 7,  
  5, 2, 1, 4, 3,  
  6, 2
]
堆的树状表示：    
        /——— 2    
    /——— 6        
   |    \——— 5    
   |        \——— 2
——— 9
   |        /——— 6
   |    /——— 7    
   |   |    \——— 3
    \——— 8        
       |    /——— 4
        \——— 6    
            \——— 1

堆顶元素为 9

元素 7 入堆后
堆的数组表示：
[
  9, 8, 7, 6, 7, 6,
  2, 1, 4, 3, 6, 2,
  5
]
堆的树状表示：
        /——— 2
    /——— 7
   |   |    /——— 5
   |    \——— 6
   |        \——— 2
——— 9
   |        /——— 6
   |    /——— 7
   |   |    \——— 3
    \——— 8
       |    /——— 4
        \——— 6
            \——— 1

堆顶元素 9 出堆后
堆的数组表示：
[
  8, 7, 7, 6, 6,
  6, 2, 1, 4, 3,
  5, 2
]
堆的树状表示：
        /——— 2
    /——— 7
   |    \——— 6
   |        \——— 2
——— 8
   |        /——— 5
   |    /——— 6
   |   |    \——— 3
    \——— 7
       |    /——— 4
        \——— 6
            \——— 1

堆元素数量为 12

堆是否为空 false

js没有内置堆类

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1 Ignored Deployment

Name	Status	Preview	Comments	Updated
hello-algo	⬜️ Ignored (Inspect)			Feb 7, 2023 at 11:41AM (UTC)

[krahets]

Pending for review by @justin-tse

[justin-tse]

@what-is-me Thanks! Please address the comments.

[justin-tse]

Awesome! Thanks @what-is-me