feat: implement import page

[kyrylo-kh]

Added new page - Import page

[openedx-webhooks]

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[codecov]

Codecov Report

Patch coverage: 92.81% and project coverage change: +0.16% 🎉

Comparison is base (c47c800) 86.45% compared to head (a10f112) 86.61%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #587      +/-   ##
==========================================
+ Coverage   86.45%   86.61%   +0.16%     
==========================================
  Files         372      386      +14     
  Lines        5580     5731     +151     
  Branches     1235     1256      +21     
==========================================
+ Hits         4824     4964     +140     
- Misses        732      743      +11     
  Partials       24       24              

Files Changed	Coverage Δ
src/CourseAuthoringRoutes.jsx	100.00% <ø> (ø)
src/store.js	100.00% <ø> (ø)
src/import-page/data/thunks.js	82.35% <82.35%> (ø)
src/import-page/data/slice.js	90.90% <90.90%> (ø)
src/import-page/file-section/FileSection.jsx	93.33% <93.33%> (ø)
src/import-page/CourseImportPage.jsx	95.23% <95.23%> (ø)
src/import-page/import-stepper/ImportStepper.jsx	96.77% <96.77%> (ø)
src/import-page/data/api.js	100.00% <100.00%> (ø)
src/import-page/data/constants.js	100.00% <100.00%> (ø)
src/import-page/data/selectors.js	100.00% <100.00%> (ø)
... and 6 more

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[e0d]

Hi @Thposbsmt It looks like this PR reduces coverage and has conflicts with the base. Can you please have a look?

[KristinAoki]

Please increase code coverage for files in the data folder

[openedx-webhooks]

@Thposbsmt 🎉 Your pull request was merged! Please take a moment to answer a two question survey so we can improve your experience in the future.