msglist [nfc]: Fix an indentation nit

Author: chrisbobbe

lib/widgets/message_list.dart

@@ -745,13 +745,13 @@ class _MarkAsReadWidgetState extends State<MarkAsReadWidget> {
                   // Restate [FilledButton]'s default, which inherits from
                   // [zulipTypography]…
                   Theme.of(context).textTheme.labelLarge!
-                  // …then clobber some attributes to follow Figma:
-                  .merge(TextStyle(
-                    fontSize: 18,
-                    letterSpacing: proportionalLetterSpacing(context,
-                      kButtonTextLetterSpacingProportion, baseFontSize: 18),
-                    height: (23 / 18))
-                  .merge(weightVariableTextStyle(context, wght: 400))),
+                    // …then clobber some attributes to follow Figma:
+                    .merge(TextStyle(
+                      fontSize: 18,
+                      letterSpacing: proportionalLetterSpacing(context,
+                        kButtonTextLetterSpacingProportion, baseFontSize: 18),
+                      height: (23 / 18))
+                    .merge(weightVariableTextStyle(context, wght: 400))),
                 shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(7)),
               ).copyWith(
                 // Give the buttons a constant color regardless of whether their