Found that wget may fail on downloading the file from flaky
available servers with 500 HTTP error, like it was seen on
icu4c sources downloading, please check the issue:
https://sourceforge.net/p/forge/site-support/20071/

Found that curl successfully downloads needed files even in
such situations. Decided to use curl instead of wget tool
to avoid of such errors feather.

Also found that sourceforge site too often has issues and
responds with 500 HTTP error. Decided to use the link from
github instead of sourceforge to download the icu4c sources,
as suggested on icu4c web site.