Remove the content_not_playing issue template

.github/ISSUE_TEMPLATE/content_not_playing.md

----
-name: Content not playing correctly
-about: Issue template for a content not playing issue.
-title: ''
-labels: content not playing, needs triage
-assignees: ''
----
-
-Before filing a content issue:
-------------------------------
-- Search existing issues, including issues that are closed:
-  https://github.com/google/ExoPlayer/issues?q=is%3Aissue
-- Consult our supported formats page, which can be found at
-  https://exoplayer.dev/supported-formats.html.
-- Learn how to create useful log output by using the EventLogger:
-  https://exoplayer.dev/listening-to-player-events.html#using-eventlogger
-- Try playing your content in the ExoPlayer demo app. Information about the
-  ExoPlayer demo app can be found here:
-  http://exoplayer.dev/demo-application.html.
-
-When reporting a content issue:
------------------------------
-Fill out the sections below, leaving the headers but replacing the content. If
-you're unable to provide certain information, please explain why in the relevant
-section. We may close issues if they do not include sufficient information.
-
-### [REQUIRED] Content description
-Describe the content and any specifics you expected to play but did not. This
-could be the container or sample format itself or any features the stream has
-and you expect to play, like 5.1 audio track, text tracks or drm systems.
-
-### [REQUIRED] Link to test content
-Provide a JSON snippet for the demo app’s media.exolist.json file, or a link to
-media that reproduces the issue. If you don't wish to post it publicly, please
-submit the issue, then email the link to dev.exoplayer@gmail.com using a subject
-in the format "Issue #1234", where "#1234" should be replaced with your issue
-number. Provide all the metadata we'd need to play the content like drm license
-urls or similar. If the content is accessible only in certain countries or
-regions, please say so.
-
-### [REQUIRED] Version of ExoPlayer being used
-Specify the absolute version number. Avoid using terms such as "latest".
-
-### [REQUIRED] Device(s) and version(s) of Android being used
-Specify the devices and versions of Android on which you expect the content to
-play. If possible, please test on multiple devices and Android versions.
-
-### [REQUIRED] A full bug report captured from the device
-Capture a full bug report using "adb bugreport". Output from "adb logcat" or a
-log snippet is NOT sufficient. Please attach the captured bug report as a file.
-If you don't wish to post it publicly, please submit the issue, then email the
-bug report to dev.exoplayer@gmail.com using a subject in the format
-"Issue #1234", where "#1234" should be replaced with your issue number.