MM-31064: Simplify indentation (#16565)

* MM-31064: Simplify indentation

Reduce indentation where possible.

```release-note
NONE
```

Command ran to verify:
golangci-lint run --disable-all --enable golint --max-issues-per-linter=10000 --max-same-issues=100000 ./... | grep "block ends with a return state"

https://mattermost.atlassian.net/browse/MM-31064

* incorporate review comments

* enable golint for outdent rule

* fix remaining issues

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

api4/apitestlib.go

@@ -1141,15 +1141,13 @@ func (th *TestHelper) SetupChannelScheme() *model.Scheme {
 }
 
 func (th *TestHelper) SetupScheme(scope string) *model.Scheme {
-	scheme := model.Scheme{
+	scheme, err := th.App.CreateScheme(&model.Scheme{
 		Name:        model.NewId(),
 		DisplayName: model.NewId(),
 		Scope:       scope,
-	}
-
-	if scheme, err := th.App.CreateScheme(&scheme); err == nil {
-		return scheme
-	} else {
+	})
+	if err != nil {
 		panic(err)
 	}
+	return scheme
 }

api4/team_test.go

@@ -631,10 +631,9 @@ func TestUpdateTeamPrivacy(t *testing.T) {
 				if test.errChecker != nil {
 					test.errChecker(t, resp)
 					return
-				} else {
-					CheckNoError(t, resp)
-					CheckOKStatus(t, resp)
 				}
+				CheckNoError(t, resp)
+				CheckOKStatus(t, resp)
 				require.Equal(t, test.wantType, team.Type)
 				require.Equal(t, test.wantOpenInvite, team.AllowOpenInvite)
 				if test.wantInviteIdChanged {