fix(carbon): fix time picker initial value

[GilbertCherrie]

Fixes: #1155

Description:
Fixed the AM/PM select initial value for the time picker component.

[DataDrivenFormsBot]

A new version (fix) will be released: v3.15.4 [DataDrivenFormsBot]

[codecov]

Codecov Report

Merging #1157 (bf8d30e) into master (03df194) will decrease coverage by 0.01%.
The diff coverage is 95.45%.

❗ Current head bf8d30e differs from pull request most recent head 6abea25. Consider uploading reports for the commit 6abea25 to get more accurate results

@@            Coverage Diff             @@
##           master    #1157      +/-   ##
==========================================
- Coverage   94.89%   94.88%   -0.02%     
==========================================
  Files         209      209              
  Lines        3567     3579      +12     
  Branches     1234     1241       +7     
==========================================
+ Hits         3385     3396      +11     
- Misses        182      183       +1     

Impacted Files	Coverage Δ
...nt-mapper/src/time-picker-date/time-picker-date.js	100.00% <ø> (ø)
...nt-mapper/src/time-picker-base/time-picker-base.js	95.83% <95.45%> (-4.17%)	⬇️

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[rvsia]

Hello,

thank you for this PR.

however, several changes are required:

1. time-picker-base file is just a styling component with no internal logic, to implement this fix we have to update time-picker-date.js component (string variant is already working well)

2. initialLoad prop is not neccesary, we can just use initialValue (resp. input.value)

3. for setting the correct value we can just update the format state variable in an init function

before

const [format, selectFormat] = useState('AM');

after

const [format, selectFormat] = useState(() => input.value?.getHours?.() >= 12 ? “PM” : “AM”);

[GilbertCherrie]

@rvsia I tried out your suggestions and it does not seem to be working. If you would like to test it out I pushed the changes along with the test data I was using in the carbon component mapper sandbox. Not really sure why it is not working initially I was trying out something similar to what your suggestions mentioned but it didn't work which is why I ended up with the complicated code in my first commit.

[rvsia]

closing in favor of #1160