Treat fediverse usernames as case-insensitive (#2155)

* treat fediverse usernames as case-insensitive for auth

* add test for case insensitive, clean up duplicate import in federverse auth controller

* fix test, there was an issue with state when all the tests were run

auth/fediverse/fediverse_test.go

@@ -1,6 +1,9 @@
 package fediverse
 
-import "testing"
+import (
+	"strings"
+	"testing"
+)
 
 const (
 	accessToken     = "fake-access-token"
@@ -58,3 +61,18 @@ func TestSingleOTPFlowRequest(t *testing.T) {
 		t.Error("Second registration should not be permitted.")
 	}
 }
+
+func TestAccountCaseInsensitive(t *testing.T) {
+	account := "Account"
+	accessToken := "another-fake-access-token"
+	r1, _ := RegisterFediverseOTP(accessToken, userID, userDisplayName, account)
+	_, reg1 := ValidateFediverseOTP(accessToken, r1.Code)
+
+	// Simulate second auth with account in different case
+	r2, _ := RegisterFediverseOTP(accessToken, userID, userDisplayName, strings.ToUpper(account))
+	_, reg2 := ValidateFediverseOTP(accessToken, r2.Code)
+
+	if reg1.Account != reg2.Account {
+		t.Errorf("Account names should be case-insensitive: %s %s", reg1.Account, reg2.Account)
+	}
+}