update lower-constraints.txt

We also need to change the lower-constraint requirements to make them
py3.8 compatible. See https://bugs.launchpad.net/nova/+bug/1886298

MarkupSafe==1.1.1
paramiko==2.7.1

Change-Id: I04a0fcd98327b9f41e24e19bcab97c813760f414

Author: likui

lower-constraints.txt

@@ -38,7 +38,7 @@ jsonschema==2.6.0
 keystoneauth1==3.18.0
 kombu==4.0.0
 linecache2==1.0.0
-MarkupSafe==1.1.0
+MarkupSafe==1.1.1
 monotonic==0.6
 mox3==0.20.0
 msgpack-python==0.4.0
@@ -62,7 +62,7 @@ oslo.service==1.24.0
 oslo.utils==3.33.0
 oslotest==3.2.0
 osprofiler==1.4.0
-paramiko==2.0.0
+paramiko==2.7.1
 Paste==2.0.2
 PasteDeploy==1.5.0
 pbr==2.0.0