Replace magic number 1024 with DEFAULT_STREAM_BUFFER_SIZE in basmgr.cxx to make the code more readable and maintainable. The constant clearly indicates the purpose of this buffer size value. Change-Id: Ic307c55e2eac563200951c373a0ca545db0a9e7b Reviewed-on: https://gerrit.libreoffice.org/c/core/+/193382 Reviewed-by: Hossein <hossein@libreoffice.org> Tested-by: Jenkins