spec: increase release number

We have upgrade its build requiring package, so we need to
increase its  release number, to make it can be update by
rpm or yum command.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>

virt-viewer.spec

@@ -1,6 +1,6 @@
 Name:             virt-viewer
 Version:          7.0
-Release:          2
+Release:          3
 Summary:          A UI interface for virtualized guest OS
 License:          GPLv2+
 URL:              http://virt-manager.org/
@@ -56,5 +56,8 @@ The virt-viewer-help package contains related documents.
 %{_mandir}/man1/remote-viewer.1*
 
 %changelog
+* Tue May 19 2020 zhanghailiang<zhang.zhanghailiang@huawei.com> - 7.0-3
+- Increase release number
+
 * Sat Nov 23 2019 Jiangping Hu <hujiangping@huawei.com> - 7.0-2
 - Package init