In TestViewRepo2, convert computed timezones to local time (#24579)

This fixes up #10446; in that, the
*expected* timezone was changed to the local timezone, but the computed
timezone was left in UTC.

The result was this failure, when run on a non-UTC system:

```
	Diff:
    --- Expected
    +++ Actual
    @@ -5,3 +5,3 @@
       commitMsg: (string) (len=12) "init project",
    -  commitTime: (string) (len=29) "Wed, 14 Jun 2017 09:54:21 EDT"
    +  commitTime: (string) (len=29) "Wed, 14 Jun 2017 13:54:21 UTC"
      },
    @@ -11,3 +11,3 @@
       commitMsg: (string) (len=12) "init project",
    -  commitTime: (string) (len=29) "Wed, 14 Jun 2017 09:54:21 EDT"
    +  commitTime: (string) (len=29) "Wed, 14 Jun 2017 13:54:21 UTC"
      }
    Test:       	TestViewRepo2
```

I assume this was probably missed since the CI servers all run in UTC?

The Format() string "Mon, 02 Jan 2006 15:04:05 UTC" was incorrect: 'UTC'
isn't recognized as a variable placeholder, but was just being copied
verbatim. It should use 'MST' in order to command Format() to output the
attached timezone, which is what `time.RFC1123` has.

Author: kousu

tests/integration/repo_test.go

@@ -78,7 +78,7 @@ func testViewRepo(t *testing.T) {
 		// convert "2017-06-14 21:54:21 +0800" to "Wed, 14 Jun 2017 13:54:21 UTC"
 		htmlTimeString, _ := s.Find("relative-time.time-since").Attr("datetime")
 		htmlTime, _ := time.Parse(time.RFC3339, htmlTimeString)
-		f.commitTime = htmlTime.UTC().Format("Mon, 02 Jan 2006 15:04:05 UTC")
+		f.commitTime = htmlTime.In(time.Local).Format(time.RFC1123)
 		items = append(items, f)
 	})