Favor consistency over accuracy when displaying ISO size (GB vs GiB)

From #14548, the use of GiB was confusing. Like investigated in #9374 (closed), major software vendors (Mozilla, Google, and Microsoft) use incorrectly but consistently GiB values displayed with the GB.

Let’s do like the vast majority of the world does at the cost of being wrong.

Parent Task: #14548

Related issues

Related to #9374 (closed)

Original created by @sajolida on 15104 (Redmine)

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