poll: Simplify UI feedback on poll delay logic.

In this commit, we have traversed the decoration property
of the Ink Widget to Material and Remove the Ink Widget.
The Splash leaking out of the border has been fixed.

Fixes: #1808

# Conflicts:
#	lib/widgets/poll.dart

Author: MritunjayTiwari14

lib/widgets/poll.dart

@@ -97,18 +97,19 @@ class _PollWidgetState extends State<PollWidget> {
               padding: const EdgeInsetsDirectional.only(
                 end: 5, top: verticalPadding, bottom: verticalPadding),
               child: Material(
-                color: Colors.transparent,
+                shape: RoundedRectangleBorder(
+                  borderRadius: BorderRadius.circular(3),
+                  side: BorderSide(color: theme.colorPollVoteCountBorder)),
+                color: theme.colorPollVoteCountBackground,
+                type: MaterialType.transparency,
+                clipBehavior: Clip.antiAlias,
                 child: InkWell(
                   onTap: () => _toggleVote(option),
-                  child: Ink(
+                  child: Padding(
                     // Inner padding preserves whitespace even when the text's
                     // width approaches the button's min-width (e.g. because
                     // there are more than three digits).
                     padding: const EdgeInsets.symmetric(horizontal: 4),
-                    decoration: BoxDecoration(
-                      color: theme.colorPollVoteCountBackground,
-                      border: Border.all(color: theme.colorPollVoteCountBorder),
-                      borderRadius: BorderRadius.circular(3)),
                     child: Center(
                       child: Text(option.voters.length.toString(),
                         style: textStyleBold.copyWith(