Travis: wget from sourceforge failing for AStyle

[0xc0170]

Description

Tracking issue for current Travis failures, all PR from today are affected. The sourceforge seems to be unstable today, returning errors like connection closed, ssl fails etc.

Should fix here #7327 (exploring how to address this one)

cc @ARMmbed/mbed-os-maintainers

Issue request type

[ ] Question
[ ] Enhancement
[x] Bug

[ciarmcom]

ARM Internal Ref: MBOTRIAGE-927

[0xc0170]

Fixed via #7338