[verify ci] Fix various issues for `rally verify tempest`

1. try to fix encoding issue, need to decode Exception.output, otherwise
   cause an decode error while comparing with string.
2. Fix KeyError exception. to_html() would be raised an exception
   since some cases was skipped.
3. Update SQLAlchemy version in upper-constraints.txt

Change-Id: If4574456a07056670581e64c8bfc1672b733dfa8

tests/ci/rally_verify.py

@@ -134,12 +134,15 @@ class Step(object):
                                              stderr=subprocess.STDOUT).decode()
         except subprocess.CalledProcessError as e:
             LOG.error("Command `%s` failed." % command)
-            return Status.ERROR, e.output
+            return Status.ERROR, e.output.decode()
         else:
             return Status.PASS, stdout
 
     def to_html(self):
-        return self.HTML_TEMPLATE % self.result
+        if self.result["status"] == Status.SKIPPED:
+            return ""
+        else:
+            return self.HTML_TEMPLATE % self.result
 
 
 class SetUpStep(Step):
@@ -386,6 +389,7 @@ class ReportVerificationMixin(Step):
         self.CALL_ARGS["uuids"] = " ".join(
             [v["uuid"] for v in self.rapi.verification.list()])
         print(self.COMMAND % self.CALL_ARGS)
+        self.result["out"] = "<None>"
 
     def run(self):
         super(ReportVerificationMixin, self).run()

upper-constraints.txt

@@ -126,8 +126,8 @@ setuptools===40.4.3
 simplejson===3.16.0
 six===1.11.0
 Sphinx==1.8.5;python_version=='2.7'
-SQLAlchemy===1.2.12
-sqlalchemy-migrate===0.11.0
+SQLAlchemy===1.3.4
+sqlalchemy-migrate===0.12.0
 sqlparse===0.2.4
 stevedore===1.29.0
 subprocess32===3.5.2