Changed dynamic tags to add data-marko-key and to selfclose properly

[agliga]

Description

For dynamic split components, data-marko-key was not being added and you could not access data from that template. This came to light because of the change we did to body-only-if which we moved to be a dynamic component.
Split up beginElementDynamic and added data-marko-key when component is in browser.

I also fixed the selfclosing tags using a library to see which fields are self-closing and added those properly.

Cleaned up the redundant params also.

Added tests for each case, for both empty tags and non empty
Added a test for self-closing.

Checklist:

• I have read the CONTRIBUTING document and have signed (or will sign) the CLA.
• I have updated/added documentation affected by my changes.
• I have added tests to cover my changes.

[codecov]

Codecov Report

Merging #1499 into master will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1499      +/-   ##
==========================================
- Coverage   90.50%   90.47%   -0.03%     
==========================================
  Files         352      352              
  Lines       12583    12593      +10     
==========================================
+ Hits        11388    11394       +6     
- Misses       1195     1199       +4     

Impacted Files	Coverage Δ
src/runtime/html/AsyncStream.js	89.13% <0.00%> (-1.14%)	⬇️

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