Convert brand store App component to TypeScript

[steverydz]

Done

Converted the brand store App component to TypeScript

How to QA

• Go to https://snapcraft-io-4308.demos.haus/admin
• Check that the app renders without errors

[webteam-app]

Demo starting at https://snapcraft-io-4308.demos.haus

[codecov]

Codecov Report

Merging #4308 (36f9921) into main (d5e9094) will decrease coverage by 4.95%.
The diff coverage is 50.00%.

❗ Current head 36f9921 differs from pull request most recent head d8b14c5. Consider uploading reports for the commit d8b14c5 to get more accurate results

@@            Coverage Diff             @@
##             main    #4308      +/-   ##
==========================================
- Coverage   87.56%   82.62%   -4.95%     
==========================================
  Files          95      185      +90     
  Lines        6653     9627    +2974     
  Branches        0      770     +770     
==========================================
+ Hits         5826     7954    +2128     
- Misses        827     1552     +725     
- Partials        0      121     +121     

Flag	Coverage Δ
javascript	71.55% <50.00%> (?)
python	87.56% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
static/js/brand-store/slices/brandStoreSlice.ts	9.52% <0.00%> (ø)
static/js/brand-store/store/index.ts	100.00% <ø> (ø)
static/js/brand-store/hooks/index.ts	100.00% <100.00%> (ø)

... and 87 files with indirect coverage changes

[chillkang]

LGTM 👍