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>

utils/html.go

@@ -43,11 +43,11 @@ func NewHTMLTemplateWatcher(directory string) (*HTMLTemplateWatcher, error) {
 		return nil, err
 	}
 
-	if htmlTemplates, err := template.ParseGlob(filepath.Join(templatesDir, "*.html")); err != nil {
+	htmlTemplates, err := template.ParseGlob(filepath.Join(templatesDir, "*.html"))
+	if err != nil {
 		return nil, err
-	} else {
-		ret.templates.Store(htmlTemplates)
 	}
+	ret.templates.Store(htmlTemplates)
 
 	go func() {
 		defer close(ret.stopped)