all: Fix various user-facing and non-user-facing typos (#8509)

Found via `codespell -q 3 -S lang,./gui/default/vendor -L benchs,bu,inflight,ro`

lib/fs/mtimefs_test.go

@@ -205,7 +205,7 @@ func TestMtimeFSInsensitive(t *testing.T) {
 			t.Error("Should not have failed:", err)
 		}
 
-		// Check that we get back the mtime we set, if we were supposed to succed.
+		// Check that we get back the mtime we set, if we were supposed to succeed.
 		info, err := fs.Lstat("testdata/FILE")
 		if err != nil {
 			t.Error("Lstat shouldn't fail:", err)