www/aria2: update to 1.28.0

• Expose SSH2 option (appeared in 1.19.0)
• Chase HTTP redirect in MASTER_SITES
• Convert USE_OPENSSL=yes into USES+=ssl

Changes: https://github.com/aria2/aria2/compare/release-1.23.0...release-1.28.0
Changes: https://github.com/aria2/aria2/releases
PR: 212960
Submitted by: lightside@gmx.com
Approved by: maintainer timeout (3 weeks)