Cache the function wrapper, no need to recreate each render.

[agubler]

Type: bug/feature

The following has been addressed in the PR:

• There is a related issue
• All code has been formatted with prettier as per the readme code style guidelines
• Unit or Functional tests are included in the PR

Description:

There is no need to recreate the property function wrapper each render, in addition this is causing issues with the custom element wrapper because the functions will always be referentially different.

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[codecov]

Codecov Report

Merging #903 (51aa1c2) into master (29854e3) will increase coverage by 0.00%.
The diff coverage is 88.88%.

@@           Coverage Diff           @@
##           master     #903   +/-   ##
=======================================
  Coverage   94.60%   94.61%           
=======================================
  Files         127      127           
  Lines        8141     8145    +4     
  Branches     1900     1901    +1     
=======================================
+ Hits         7702     7706    +4     
  Misses        439      439           

Impacted Files	Coverage Δ
src/core/vdom.ts	97.79% <88.88%> (+<0.01%)	⬆️

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