feat(angular): paginated list component (#310)

### 🎯 Goal

This PR only affects the Angular SDK. As part of reactions-v2 I created
two, lightweight (in terms of CSS) components:
- Paginated list
- User list

This PR contains the CSS for those.

### 🛠 Implementation details

_Provide a description of the implementation_

### 🎨 UI Changes

_Add relevant screenshots_

Make sure to test with both Angular and React (with both `MessageList`
and `VirtualizedMessageList` components) SDKs

Author: szuperaz

src/v2/styles/_base.scss

@@ -28,3 +28,34 @@ stream-icon-placeholder {
   justify-content: center;
   align-items: center;
 }
+
+.stream-chat__paginated-list {
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+  overflow-x: hidden;
+  overflow-y: scroll;
+  max-height: 100%;
+  min-height: 0;
+  gap: var(--str-chat__spacing-2);
+
+  .str-chat__loading-indicator {
+    margin: auto;
+  }
+}
+
+stream-paginated-list {
+  height: 100%;
+  max-height: 100%;
+}
+
+stream-user-list {
+  height: 100%;
+  max-height: 100%;
+
+  .str-chat__user-list-item {
+    display: flex;
+    align-items: center;
+    gap: var(--str-chat__spacing-2);
+  }
+}