Correct the unit of file size from "kb" (maybe "kilo bits") to "KB"

[fzyzcjy]

The error message when enabling "invert oversized images" tells us how many extra space the image uses. That is quite helpful! However, when I read ...an additional 1234kb...I thought that means kilo bits (since in network programming kb and kB are definitely different and should be taken with care). However, after reading the source code, I suddenly realized that it is kilo bytes. Thus, this PR is here to ensure that people do not misunderstand the unit.

List which issues are fixed by this PR. You must list at least one issue.
Fixes #76032

If you had to change anything in the flutter/tests repo, include a link to the migration guide as per the breaking change policy.
N/A

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[flutter-dashboard]

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[goderbauer]

LGTM

Looks like this is failing some tests, though. Can you please fix those?

[fzyzcjy]

@goderbauer Thanks! I only change 2 characters in a literal String, so I am a bit confused why it the tests are failed... I have looked at the CI logs, but seems no clues (since I am not very familiar with all the infrastructures of Flutter). Could you please give some hints?

[goderbauer]

There appear to be tests that verify the error message you're modifying. You can probably reproduce this locally by going into the packages/flutter directory and running flutter test there.

[fzyzcjy]

@goderbauer Thanks! I will have a look

[fzyzcjy]

@goderbauer Hi all checks have passed!

[fzyzcjy]

Wait a bit... The flutter-build fails? Hours ago it was all green...

Is that related to my PR or not? When I click "Details" I see a dashboard, which seems to have no relationship to me...