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>

web/saml.go

@@ -56,13 +56,13 @@ func loginWithSaml(c *Context, w http.ResponseWriter, r *http.Request) {
 		relayState = b64.StdEncoding.EncodeToString([]byte(model.MapToJson(relayProps)))
 	}
 
-	if data, err := samlInterface.BuildRequest(relayState); err != nil {
+	data, err := samlInterface.BuildRequest(relayState)
+	if err != nil {
 		c.Err = err
 		return
-	} else {
-		w.Header().Set("Content-Type", "application/x-www-form-urlencoded")
-		http.Redirect(w, r, data.URL, http.StatusFound)
 	}
+	w.Header().Set("Content-Type", "application/x-www-form-urlencoded")
+	http.Redirect(w, r, data.URL, http.StatusFound)
 }
 
 func completeSaml(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -80,12 +80,12 @@ func completeSaml(c *Context, w http.ResponseWriter, r *http.Request) {
 	relayProps := make(map[string]string)
 	if len(relayState) > 0 {
 		stateStr := ""
-		if b, err := b64.StdEncoding.DecodeString(relayState); err != nil {
+		b, err := b64.StdEncoding.DecodeString(relayState)
+		if err != nil {
 			c.Err = model.NewAppError("completeSaml", "api.user.authorize_oauth_user.invalid_state.app_error", nil, err.Error(), http.StatusFound)
 			return
-		} else {
-			stateStr = string(b)
 		}
+		stateStr = string(b)
 		relayProps = model.MapFromJson(strings.NewReader(stateStr))
 	}