[BD-46] change searchfield`s background color

[khudym]

Description

Change searchfield`s background color to white (including button)

Issue

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[viktorrusakov]

@khudym Please, update snapshots for the component, because tests pipeline is failing. Also, you need to fix your last commit message, it must start with one of the allowed keywords, you can read more here.

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (0ef92d9) 91.69% compared to head (9a7ce31) 91.69%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2597   +/-   ##
=======================================
  Coverage   91.69%   91.69%           
=======================================
  Files         235      235           
  Lines        4214     4214           
  Branches     1021     1021           
=======================================
  Hits         3864     3864           
  Misses        346      346           
  Partials        4        4           

Files Changed	Coverage Δ
src/SearchField/SearchFieldAdvanced.jsx	90.47% <ø> (ø)

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[edx-semantic-release]

🎉 This PR is included in version 21.1.6 🎉

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[edx-semantic-release]

🎉 This PR is included in version 22.0.0-alpha.6 🎉

The release is available on:

• npm package (@alpha dist-tag)
• GitHub release

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