Fix mxid colors for dark theme

Signed-off-by: Ajay Bura <ajbura@gmail.com>

src/app/atoms/avatar/Avatar.jsx

@@ -32,7 +32,7 @@ function Avatar({
                 iconSrc !== null
                   ? <RawIcon size={size} src={iconSrc} />
                   : text !== null && (
-                    <Text variant={textSize} primary>
+                    <Text variant={textSize} weight="medium" primary>
                       {twemojify([...text][0])}
                     </Text>
                   )

src/app/atoms/avatar/Avatar.scss

@@ -45,7 +45,7 @@
     border-radius: inherit;
 
     .text {
-      color: var(--tc-primary-high);
+      color: var(--bg-surface);
     }
   }
 }