Image picker feature, add file accept

[dqmmpb]

First of all, thank you for your contribution! :-)

Please makes sure that these checkboxes are checked before submitting your PR, thank you!

• Make sure that you follow antd's code convention.
• Run npm run lint and fix those errors before submitting in order to keep consistent code style.
• Rebase before creating a PR to keep commit history clear.
• Add some descriptions and refer relative issues for you PR.

Extra checklist:

if isBugFix :

• Make sure that you add at least one unit test for the bug which you had fixed.

elif isNewFeature :

• Update API docs for the component.
• Update/Add demo to demonstrate new feature.
• Update TypeScript definition for the component.
• Add unit tests for the feature.

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This change is 

[codecov]

Codecov Report

Merging #2269 into master will not change coverage.
The diff coverage is 50%.

@@           Coverage Diff           @@
##           master    #2269   +/-   ##
=======================================
  Coverage   57.79%   57.79%           
=======================================
  Files         260      260           
  Lines        4459     4459           
  Branches     1178     1178           
=======================================
  Hits         2577     2577           
  Misses       1881     1881           
  Partials        1        1

Flag	Coverage Δ
#rn	60.78% <ø> (ø)	⬆️
#web	55.23% <50%> (ø)	⬆️

Impacted Files	Coverage Δ
components/image-picker/PropsType.tsx	0% <ø> (ø)	⬆️
components/image-picker/index.tsx	33.64% <50%> (ø)	⬆️

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