BaseTools/UserManuals: update with new report bug mail address

BaseTools/UserManuals: update with new report bug mail address

The .rtf files in BaseTools/UserManuals still tell users to Report bugs
to sourceforge mail address. Since we no longer use the sourceforge
mailing lists we should update it.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>