tst_QTextStream: reduce the runtime of pos3LargeFile()6.10

This test function exhibits quadratic behavior in the size of the test
file, and takes 5min on my laptop to execute for the 50KiB file,
pointlessly spinning the CPU while not testing anything (the pos()
result is not even checked).

Save some CO2 by reducing the test file size to 5KiB. This reduces the
run time on my machine to 1s (from 5min!) and should make the test run
fast enough for emulated platforms, too, so remove the QSKIP.

As a drive-by, fix grammar in the code comment, and spacing around
operators.

Amends the start of the public history for the problem itself and
71bd06d516a2410ae0ea698e79dcb94aba9bc5b4 for the QSKIP.

Pick-to: 6.9 6.8 6.5 5.15
Fixes: QTBUG-138428
Task-number: QTBUG-138435
Change-Id: Iea49f5ba41aea1c372a9dd9b5472d7205f492b99
Reviewed-by: Thiago Macieira <[email protected]>
(cherry picked from commit 54204fc7943ef91aa9b665b1287b870680697db4)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>

0 files changed, 0 insertions, 0 deletions