set maxwidth on feed context string (#8817)

src/components/PostControls/DiscoverDebug.tsx

···
         hitSlop={10}
         style={[
           a.absolute,
-          a.bottom_0,
-          {zIndex: 1000},
+          {zIndex: 1000, maxWidth: 65, bottom: -4},
           gtMobile ? a.right_0 : a.left_0,
         ]}
         onPress={e => {
···
           Toast.show(t`Copied to clipboard`, 'clipboard-check')
         }}>
         <Text
+          numberOfLines={1}
           style={{
             color: theme.palette.contrast_400,
             fontSize: 7,