Fix deprecations and minor linter warnings (#1438)

* Fix api deprecations

* Fix minor lineter warning

When handling the error of `evict()` return false inside the onError
function of catchError so that the Future completes with false to
indicate that the value wasn't removed successfully.

example/lib/pages/tile_builder_example.dart

@@ -38,15 +38,15 @@ class _TileBuilderPageState extends State<TileBuilderPage> {
  if (showCoords)
  Text(
  '${coords.x.floor()} : ${coords.y.floor()} : ${coords.z.floor()}',
- style: Theme.of(context).textTheme.headline5,
+ style: Theme.of(context).textTheme.headlineSmall,
  ),
  if (loadingTime)
  Text(
  tile.loaded == null
  ? 'Loading'
  // sometimes result is negative which shouldn't happen, abs() corrects it
  : '${(tile.loaded!.millisecond - tile.loadStarted.millisecond).abs()} ms',
- style: Theme.of(context).textTheme.headline5,
+ style: Theme.of(context).textTheme.headlineSmall,
  ),
  ],
  ),

lib/src/layer/tile_layer/tile.dart

@@ -71,6 +71,7 @@ class Tile {
  try {
  imageProvider.evict().catchError((Object e) {
  debugPrint(e.toString());
+ return false;
  });
  } catch (e) {
  // this may be never called because catchError will handle errors, however

lib/src/layer/tile_layer/tile_builder.dart

@@ -95,7 +95,7 @@ Widget coordinateDebugTileBuilder(
  Center(
  child: Text(
  readableKey,
- style: Theme.of(context).textTheme.headline5,
+ style: Theme.of(context).textTheme.headlineSmall,
  ),
  ),
  ],
@@ -127,7 +127,7 @@ Widget loadingTimeDebugTileBuilder(
  Center(
  child: Text(
  time,
- style: Theme.of(context).textTheme.headline5,
+ style: Theme.of(context).textTheme.headlineSmall,
  ),
  ),
  ],