Failures on Make `UriData` more case-insensitive.

[lrhn]

There are new test failures on Make UriData more case-insensitive..

The tests

LibTest/core/Uri/Uri.dataFromBytes_A01_t02 RuntimeError (expected Pass)
LibTest/core/UriData/UriData.fromBytes_A01_t02 RuntimeError (expected Pass)

are failing after the linked CL has changed the visible behavior of a data: URI. Extra case-normalization means that the casing of the content-type has changed. That fields is specified as being case-insensitive, so there should be no breakage other than tests expecting a specific case.

Consider changing the tests to ignore the case of the string, rather than just expect the new result.