Fix: Resolve extractor media source error on exoplayer utils

Error Message: "e: /Users/.../WordPress-Android/WordPress/src/main/java/
org/wordpress/android/ui/media/ExoPlayerUtils.kt: (10, 45):
Unresolved reference: ExtractorMediaSource"

As part of the 'ExoPlayer' version '2.14.0' the deprecated
'ExtractorMediaSource' got removed in favor of 'ProgressiveMediaSource'.

Release Notes: https://github.com/google/ExoPlayer/releases/tag/r2.14.0

WordPress/src/main/java/org/wordpress/android/ui/media/ExoPlayerUtils.kt

@@ -7,7 +7,7 @@ import android.net.Uri
 import com.google.android.exoplayer2.C
 import com.google.android.exoplayer2.C.ContentType
 import com.google.android.exoplayer2.offline.FilteringManifestParser
-import com.google.android.exoplayer2.source.ExtractorMediaSource
+import com.google.android.exoplayer2.source.ProgressiveMediaSource
 import com.google.android.exoplayer2.source.MediaSource
 import com.google.android.exoplayer2.source.dash.DashMediaSource.Factory
 import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser
@@ -56,7 +56,7 @@ class ExoPlayerUtils @Inject constructor(
             C.TYPE_HLS -> HlsMediaSource.Factory(defaultDataSourceFactory)
                 .setPlaylistParserFactory(DefaultHlsPlaylistParserFactory())
                 .createMediaSource(uri)
-            C.TYPE_OTHER -> ExtractorMediaSource.Factory(defaultDataSourceFactory).createMediaSource(uri)
+            C.TYPE_OTHER -> ProgressiveMediaSource.Factory(defaultDataSourceFactory).createMediaSource(uri)
             else -> {
                 throw IllegalStateException("$UNSUPPORTED_TYPE $type")
             }