Remove support for deprecated unmarshaler

[bogdandrutu]

Updates #2540

[codecov]

Codecov Report

Merging #2591 (f03072b) into main (bf6dc58) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2591      +/-   ##
==========================================
- Coverage   92.03%   92.03%   -0.01%     
==========================================
  Files         273      273              
  Lines       15455    15449       -6     
==========================================
- Hits        14224    14218       -6     
  Misses        849      849              
  Partials      382      382              

Impacted Files	Coverage Δ
config/config.go	98.93% <ø> (-0.02%)	⬇️
component/componenttest/example_factories.go	87.96% <100.00%> (-0.18%)	⬇️

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[tigrannajaryan]

Are there any contrib components that still use deprecated CustomUnmarshaler or all are fixed now?

[bogdandrutu]

@tigrannajaryan all are fixed and they are switched also to the helper "WithCustomUnmarshaler" from components helpers